Thursday, September 30, 2010  

The heat wave is over -- temperatures were in the 70s. Running at lunchtime was much less of an ordeal than it had been in recent days. 

Speaking of running: it's time once again for the Harvest Fair 10K! That is a 6.2-mile footrace held annually in Santa Rosa. I just registered for it on line -- now my big challenge is to avoid oversleeping on Sunday and missing the thing.

My finishing time in the race last year was 57:01. I'd like to see if I can do better this time. I don't think I'll ever be a fast runner, but that's no reason why I shouldn't try for some degree of improvement. My running buddies have been getting faster lately, and I haven't, or at least not as much as they have. It's kind of embarrassing. Typically I keep up with them for the first half of a run, and then I fall behind. Sometimes way behind. They don't tease me about it -- but other people I work with, who encounter me out there when they're walking or running the other direction, are not shy about pointing out that my companions are getting way ahead of me and I'd better put on some speed. (That happened today, for example.)

I have a lot of conflicting feelings about this speed issue. In principle, it would be nice to be fast enough to keep up with whoever I want to run with. On the other hand, I'm not willing to hurt myself trying to achieve that. I have come to suspect that running really fast is not the best way to ensure that you will be able to keep running as you get older.

Apparently a lot of doctors (or rather, a lot of insurance corporations deciding what doctors can and can't do) are trying to stop diabetes patients from testing their blood sugar very often. Patients complain about this all the time on diabetes forums.

What people (and I must assume that those who run insurance corporations are, in some loose sense, "people") don't seem to understand about diabetes management is the psychological difficulty involved. It basically requires you to do precisely what you don't feel like doing -- all day, every day, for the rest of your life. This turns out not to be an easy assignment, surprisingly enough. Maybe those who haven't tried living that way should not be in such a hurry to make decisions on behalf of those who are forced to live that way.

Given the extreme psychological demands of diabetes management, it should come as no surprise that many people fail at it. It should also come as no surprise that those who don't fail at it tend to rely heavily upon on various tricks and gimmicks to motivate themselves to do what's needed, and keep themselves on track. If testing is one of those gimmicks, so be it. It might not seem to you as if somebody whose blood sugar is obviously well-controlled needs to keep testing in order to maintain that kind of control -- but if you're not in his shoes, maybe you're not in a very good position to asses his needs.

Test strips may not be as cheap as we'd like them to be, but it's hard for me to believe that the cost of testing is anywhere near the cost of not testing.

Wednesday, September 29, 2010  

The slow cooling trend continues -- it was only about 90 when we went running today. But it was a tough hilly run, and I felt pretty wiped-out by it. Believe it or not, that was a good thing.

I'd had such a stressful morning at work that doing a really difficult run was exactly what I needed. It made me feel better, allowed me to overcome the feeling of panic I was having about a project deadline on Friday which it didn't appear I could meet. So after the run -- and a cool shower, and a waiting period for my shirt to dry off, so it didn't look like I was having a heart attack -- I went in to see the project manager, and told him frankly that I didn't think I could meet the Friday deadline, and told him what the fallback plan was as I saw it. He took this in calmly (he takes in everything calmly, that's probably why they made him a project manger), and he told me that (1) our Friday deadline is probably pushing out to next week anyway, and (2) my fallback plan is acceptable.

And so, my blood pressure this evening is 118/75 instead of 138/95, or wherever it would have been if I hadn't gone running, and hadn't relaxed enough to face reality and admit what my situation on the project actually was, instead of trying desperately to pretend everything was under control.

Exercise is often recommended as a means of reducing stress and preventing depression (and it does help greatly in those areas), but it has a less-recognized role in helping people face reality. If you need something to get you reconnected with reality, I'm pretty sure that running on steep hills in hot weather is an excellent way to do that. It works for me, anyway.

This image...

...was sent to me as one of a set of examples of students' failing answers to test questions. It seems likely to me that this particular wrong answer springs not from an innocent misunderstanding of the assignment, but from a satirical disrespect for numbers in general.

A lot of people are very good at not taking numbers seriously. The mere fact that information is presented in quantitative form is enough for many people to dismiss it as "abstract", which for them means that it isn't interesting or important, and they shouldn't have to be bothered with it.

Because they take this attitude, they feel comfortable ignoring information which has serious implications for them. For example, those who have a strong emotional commitment to the idea that diabetes is a purely genetic disease, and that lifestyle has nothing to do with it, are unlikely to appreciate, or even notice, what has been going with the prevalence of diabetes in recent years:

It seems like a pretty striking upward trend to me. It's pretty hard to account for a steady increase of that sort, in prevalence of a purely genetic disease. Purely genetic diseases tend not to have epidemics. They don't ramp up dramatically over a 25-year period, because you can't fit a lot of generations into so small a span of time. Unless the people who carry the genes for that disease are reproducing a lot faster than people who don't, gene prevalence canot possibly be increasing as fast as disease prevalence is.

Therefore, if diabetes prevalence is rising rapidly, something other than genetic factors has to be driving the increase; somehow or other, people are living differently than they once did, and an increased prevalence of diabetes is the result. We have to face that.

Well, actually, we don't have to face it, especially if we have succeeded in remaining unaware of the rising diabetes prevalence (after all, this is numerical information and therefore meaningless). But we should face it.

Tuesday, September 28, 2010  

I reported that the temperature was 102 degrees yesterday -- and I was mistaken. It was actualy 104, and it broke a local heat record for September 27 which was set when Kennedy was president. I guess it's only fair (since the rest of the country was having major heat waves in August, when it was cool here) that we should have scorching temperatures here now that the rest of the country is cooling off.

Today it was a mere 103 degrees. Even so, we decided to make our mid-day run a little bit easier by starting it at 11 AM. It was no hotter than about 92 by the time we finished the run.

We added a little extension to our route, to climb up the hill to the Paradise Ridge winery. Alas, our schedules didn't allow us enough time to go into the tasting room, and refresh ourselves with a nice cool Sauvignon Blanc. We paused just long enough to enjoy the view of the valley to the west, and to savor the breeze that was blowing up there. Then: back down the hill to the office.

Some obscure impulse made me want to see if I could get away with having a bowl of chili for lunch. I thought the carbs in the beans might be a little excessive for me, but apparently not -- my glucose was only 96 afterwards. The hard run may have had something to do  with it.

Ever since my diabetes diagnosis -- or rather, ever since I changed the way I was living following my diabetes diagnosis -- I have been getting pretty much the same sort of results on my lipids tests. My altered lifestyle brought about a sharp decline in triglycerides and "bad" cholesterol, and these things have stayed in the normal range since then. My "good" cholesterol (HDL) remained low for a while, but eventually climbed up into the normal range, once I had increased my exercise level into a high enough range.

And that is how things have remained ever since. But the thing is, my eating habits have fluctuated considerably over that time. I have tried different degrees of vegetarianism (a pretty low degree, just lately) and different degrees of carbohydrate restriction. I have not yet done the Atkins-style extreme low-carb diet, and I'm resisting it (I have a hard time seeing myself as a modern-day Nanook of the North, crouching in his igloo gnawing on blubber), but I can't say I'll never give it a shot.

So, my diet has varied, but my lipid-test results have been strikingly consistent. I can't help noticing that the constant element in all this as been exercise. Whatever I was eating, or choosing not to eat, I have been exercising up a storm.

This leads me to think that (in my case, at least) exercise has more influence on my lipids than diet does.

I realize that this flies in the face of what most people believe about cholesterol and such, and I also realize that it may be worng (or right only about some people). I'm just mentioning it for whatever it is worth.

Monday, September 27, 2010  

In last week's episode, Tom had given another blood sample at the lab, so that they could do the A1c test they'd forgotten to run on the 21st. So here's the lab report:

5.6 is in the normal range defined by this lab for their version of the A1c test, so my doctor is satisfied. But I'm disappointed, because I wanted to be lower than last year rather than higher (the result was 5.3 last year). I admit that I'm being a little fussy about this, but I feel strongly that I can do better than that, and should do better than that.

So, if I'm going to follow the kind of advice I give to other people, it's time for me to think about why this result was up when I wanted it to be down, and then think about what I'm going to change in order to get a better result next time.

So, why was it up? Especially when my test results have been low? Well, my vacation last month was a time of minimal exercise. I didn't skip any exercise days, but the exercise I did was minimal -- much less than what I usually do when I'm not on vacation. And my meals were the meals served at camp -- big meals, and mostly high-carb meals. I didn't do post-prandial tests that week (they probably would have been alarmingly high), and my fasting tests were above my usual standard. I thought at the time that I was entitled to relax my standards while I was on vacation, after being such a good boy in recent months, but you can't relax your standards and then not expect it to influence your A1c result.

However, my vacation wasn't long enough to account for all of the difference on the A1c test -- I think something else contributed to the upward trend, and I think I know what that something is. Although I've started doing post-prandial tests lately, and getting good results, I'm only testing after one meal a day (my prescription for test strips doesn't allow for more frequent testing than that). Arguably, it ought to be enough. But if I'm only testing after one meal per day, then I'm likely to make an unsconscious adjustment, and concentrate my carbs in the meals that are going to go untested. For example, I rarely test after breakfast, mainly because the timing is such a problem with my work schedule -- but breakfast is the hardest meal to make low-carb.

The thing is, when I test after a meal, I know that I'm going to be doing that before I eat the meal. Maybe what I should do is introduce a random element into this: toss a coin after a meal, and test if it's heads and if I haven't already done a test today.

Of course, my devious subconscious may deal with this by minimizing the carbs in every meal, in case I have to test after it. Well, if that happens, then it will be a good thing, won't it?

It was a hot day -- 102 degrees (our August was absurdly cool, so now we're finally having August weather in late September). Running at lunchtime was a bit of a challenge, but we ran a little early today to see if we could give ourselves a break. It worked, sort of. It was only 93 degrees during our run; the real heat didn't begin until later.

It was still hot in the evening; my yoga teacher recognized that people were wilting, and she gave us a lot stretches to do that are performed lying down. (A lot of the standing poses you do in yoga cause you to heat up -- in fact, in the winter people use them for just that purpose. None of that tonight, thank goodness.) Anyway, the stretches we were doing tonight were mostly focused on the hips, which is great because I need that. I always need that, because I do a lot of running, and running can easily make my hips sore. I look upon yoga as a good cure for that.

I spent much of the weekend doing musical things, and coping with very hot weather. At the Sebastopol Celtic Festival on Saturday, there was (for reasons never explained) no canopy to give the audience any shade. However, if you sat on the ground right at the foot of the stage, there was a shadow on you, so I did that -- and ended up being practically within an arm's length of the great Irish fiddler Martin Hayes.

I went back to the festival on Sunday, and afterwards drove down to San Francisco to play in an Irish music session in a pub there. But in between, I managed to fit in a hilly 5.3-mile run before sunset. The things I do for the sake of setting a good example...

Going to an Irish pub afterwards might not qualify as setting a good example, as I did not reject the ale that was offered to me there. But I did refuse to have any of the birthday cake that was brought by one of the musicians (who is a cook of some renown in the circles I travel in); saying no to that was as much of a diabetes sacrifice as I was willing to make last night. But my fasting test would have been lower this morning if I had refused the ale as well. Well, I'll try to get a better fasting test tomorrow.

Physicians With Healthier Habits More Likely to Counsel Patients About Lifestyle reads the headline in Medscape today.
I should admit at once that this is soft science at its softest: a voluntary survey, with a 36% response rate, of doctors at a single institution, summarizing what they have done as they remember it. No shortage of potential sources of error in that setup! But I'm going to discuss it anyway because it deals with an issue which interests me.

We like nothing better than to make fun of doctors who don't set a good example of healthy living. Since I have to assume that doctors themselves are aware of this, I have long wondered whether doctors' own personal habits have an influence on the lifestyle advice they give. Do overweight doctors tend to become uncomfortable with the idea of lecturing others about obesity? Do sedentary doctors tend to become uncomfortable with the idea of advising others to exercise? It wouldn't be too surprising if the fear of looking hypocritical (or ridiculous) was a big factor in determining how much emphasis doctors place on lifestyle issues.

If such an effect exists, I have no opportunity to observe it close at hand; my own doctor is highly athletic. I once ran in a hilly 10K race with him; I finished in 61 minutes, while he finished in 48 minutes and was quite disappointed that he hadn't gone faster. So, he can certainly recommend weight control and regular exercise without having to worry that anyone will accuse him of not practicing what he preaches. Perhaps for that reason, he told me from the beginning of my diabetes adventure that exercise was the key to getting this disease under control. He said he was willing to "push pills" if he had to, but his preference would be to see his patients do what was necessary to succeed without taking pills.

Might his approach have been different if he had not been exercising himself? Quite possibly so, at least according to the study reported in Medscape.

The study found that physicians, regardless of their own lifestyle, had "low confidence" in their ability to change their patients' lifestyle through counseling. Nevertheless, it was the doctors who were maintaining a normal weight, and exercising regularly, who were most likely to recommend that their patients do the same.

I guess what we need now is a study which asks whether patients respond differently to doctors who enthusiastically recommend lifestyle changes, as opposed to doctors who make weak recommendations or none. 

Friday, September 24, 2010  

Still no A1c test result today. I decided that someone must have blundered. I called the lab, asking what happened to my A1c test. At first they said that no A1c test had been ordered. Then, upon looking more closely at their records, they admitted that the test had been ordered, along with the other tests they were doing on me that day, but they had accidentally skipped the A1c. They hadn't collected enough blood to be able to run the test now, either, so I'd have to come in and give them another sample. Apparently there's no fasting requirement for an A1c test, so I drove over there immediately and gave them a little more of my hard-earned hemoglobin.

I'm kicking myself that I didn't speak up when they were taking the samples -- because I certainly had noticed that they were collecting less blood than they usually do. Why didn't I call them on it? I guess I figured that the test must have changed -- perhaps they were now using some more sophisticated measurement technology which didn't require a large blood sample. In fact, they just forgot which tests they were doing. In fairness, they did manage to do 3 of the 4 tests that my doctor asked them to do, and in some circles 75% is a passing grade. But, when it comes to medical testing, most of us want the standards to be a little higher than that.

This particular error didn't cost me anything but a day or two of impatience and confusion, and one needless trip back to the lab. Some medical errors have more far-reaching consequences than that, though. It's a reminder to me that, in a clinical setting, we should not simply take it for granted that these people must know what they're doing. They make mistakes, like anyone else does, and when something doesn't seem right to us, we shouldn't maintain a polite silence on the subject.

If it had been a surgical procedure rather than a test procedure, I'm sure I would have voiced any doubts I was having about what they were up to. A test procedure, of course, is less scary than a surgical procedure. But a test procedure is not entirely without consequences; we need to care whether or not they get it right.

Anyway, I hope they are more rigorous about the measurement process than they are about the sample-collection process. If they finally give me the results next week, and the results say that I'm pregnant, I'll know that they still haven't quite got their act together. 

How dangerous is cell phone use -- especially texting -- while driving? Some researchers at the University of North Texas Health Science Center looked into the matter. Their conclusion: between 2001 and 2007, distracted-driving incidents related to cell phone use killed 16,000 people.

Isn't that rather a lot, considering how little we are doing about the problem? If people who send text message while driving have killed more than five times as many Americans as the 9/11 hijackers did, maybe we should begin to see them as some sort of threat.

Here's a suggestion: if you text while driving and kill yourself as a result, your final text conversation has to be chiseled on your gravestone, so that your guaranteed-to-be-stupid final words are preserved forever, and generations yet unborn will be able to tell that you didn't have any more to say when you were alive than you do now that you're dead.

Of course, that's the real tragedy here: not just that people are dying, but that they are dying for the sake of an airheaded conversation that is sure to be about nothing. Every time I hear these people striding around in grocery stores, shouting "I'M IN THE BREAD AISLE! THE BREAD AISLE!" into their cell phones, I wonder who could possibly have the patience to be listening to this nonsense at the other end. And to think of actually losing your life for the sake of conversations as idiotic as that! Oh, the humanity!

Thursday, September 23, 2010  

The result of my A1c test still hasn't come in. Gosh, how long does it take them to sort my hemoglobin molecules into a sweet pile and a sour pile, and count how many are in each?

Yesterday, my doctor's scale showed me weighing nine pounds more than I weigh on my bathroom scale. Clothes cannot account for very much of that difference, as I never wear my chain-mail when I go in for a physical. I need another theory to explain this (and also to explain why everyone else on earth says that they weigh more on their doctor's scale than they do on their own).

Here's my theory: the people who sell bathroom scales deliberately calibrate them to read low. And here's why they do it: they have found that, if their scales are accurate, horrified consumers return them to the store and demand a refund. "This scale is broken!", they cry. "I know I don't weigh this much!" This sort of thing gets expensive. So, the manufacturers shave a few pounds off the result, to keep their customers happy.

I can buy a new scale, but it won't make a difference. I think there used to be an "Accurate Scales" store in San Francisco, but it went out of business for some reason.

My ridiculously low post-prandial test result this evening is the result of a ridiculously low-carb dinner. It consisted of vegetables (broccoli, cauliflower, asparagus, and mushrooms, with a small amount of olive oil and seasonings, baked in a small clay pot in the oven) and cheese.

There was a big luncheon event at work today, and the lunch was so high-carb that I was feeling guilty about it. I thought I would restore the balance by having a low-carb dinner. An hour afterward, my blood sugar was virtually the same as it had been when I did my fasting test this morning.

By the way, that's a pretty good way to prepare vegatables, and make them taste good enough to seem like the legitimate centerpiece of a meal. As a solution to The Vegetable Problem, it's a lot better than boiling them until the vitamins and flavor are gone.

One of the things I talked to my doctor about yesterday was the issue of aspirin as preventive medicine. Men of a certain age (that would be my age) have long been advised to take a low-dose aspirin, to reduce the risk of coronary heart disease. Some months back I read a study which found that doing this isn't worth it, unless you have some big cardiac risk factors -- for men not at high risk, the benefit is too small to justify the potential bleeding problems associated with daily aspirin use. Then, a study I read on Tuesday claimed that daily aspirin also reduced the risk of colon cancer. This was getting too complicated for me. I wanted to know how my doctor thought the risk/benefit analysis worked out on this issue.

He agreed that, given my good lab results and exercise fitness, I wasn't carrying a heightened cardiac risk -- and if no other issues were pertinent, taking the aspirin wouldn't be significantly better for me than not taking it. However, he said that daily aspirin did reduce the risk of colon cancer -- and this was enough to tip the balance in favor of taking the aspirin. So, he recommended that I start taking the daily low-dose aspirin again. And I will comply, good boy that I am.

It's time once again for...

Wednesday, September 22, 2010  

It was a big day for me: today I had my annual physical. It went well, as it usually does, but if you think I don't worry about these things, think again. There was a period of a few years, following my diagnosis, when I actually started looking forward to the annual physical, because I was making a striking improvement in my health, and I found it a new and refreshing experience to go into the doctor's office knowing that I was far likelier to be congratulated than scolded in there. I was the poster child at my doctor's office, the shining example of what proper diabetes self-management could accomplish. I was feeling confident and proud.

But over the years, as I got used to having good results, and came to assume that I should always expect excellence from myself, I felt less like an eager up-and-coming star, and more like a long-established star trying to hold on to his position. I became more and more inclined to worry that my success wouldn't last, and that my annual checkup would reveal that I was slipping. In recent years, I have begun to get terribly tensed-up when I go in for an appointment, waiting to find out if the lab report is going to reveal something bad that I didn't know was going on. 

Of course, the fact that I only need to see my doctor on an annual basis is significant all by itself, since diabetes patients are typically scheduled for two to four appointments a year. I don't need to be watched that closely, because at this point I have established a good track record of getting normal test results. I appreciate that I'm quite lucky in this regard, of course... but I also find that the long interval before the next appointment greatly increases the suspense I feel about it.

Yes, I realize I should have been more relaxed about today's appointment, since the results that I can collect for myself between appointments have been looking good. But I'm never entirely relaxed about this, and I wasn't today. I was plagued by the thought that my long winning streak must surely come to an end some day -- and what if today's the day?  Which, no doubt, is why my blood pressure was 138/86 in the doctor's office -- even though it's only 112/62, now that I'm home and the whole ordeal is over with.

However, to be franker than I really ought to be, all this suspense and dread is really part of a half-conscious game that I am in the habit of playing: I imagine and expect the worst, on the superstitious assumption that doing so will prevent the worst from actually happening.

At some point in my childhood I developed the feeling that the world is ruled by a law of irony: what happens is never what we expected would happen. Therefore, it is possible to ward off a calamity just by expecting it: fate steps in and prevents the calamity, just to prove us wrong. (Warning: this may not be a reliable guide to the way the universe actually operates. I'm merely reporting the idea, not recommending it.)

Anyway, my youthful mental habit of trying to prevent the worst by expecting the worst has stayed with me, for good or ill -- that's simply who I am. But perhaps I also have another, more practical motive for dwelling on the worst-case scenario: I crave the intense feeling of relief that comes when I expect the worst and it doesn't happen. So, even though I can't really prevent misfortunes simply by anticipating them, there nevertheless is a kind of emotional payoff for me in allowing myself to get terribly worried about my annual physical: when it's over, I feel great.  The relief is fantastic. My 112/62 blood pressure tonight is quite unusually low for me, and my mood is considerably more benign than it was last night. So, there's a payoff here. I don't know if the payoff is worth the cost, but I know that the payoff is real. (I suspect that's why we have neuroses: however unrewarding they might seem to anyone else, at some level we do get satisfaction out of them.)

There was a new development at my doctor's office that might make my next checkup less suspenseful: they've finally put their medical records on line, so that I will now be able to access my test results from home, preferably before I go in for my checkup, so that I won't be in a state of anxious suspense when I get there, and when they measure my blood pressure it won't be uncharacteristically high.

So here are the critical results that I got today:

All normal values, as you can see.

However, the HbA1c result is missing in action. I only had the blood samples taken yesterday, and the A1c result hasn't yet been reported back from the lab. So, I still have something to fret about! My doctor isn't fretting about it; he says that, if I can pull off a fasting result of 80 without medication, it's pretty unlikely that my A1c result will be out of the normal range. Well, yes, I'm sure he's right. But I'm enough of a perfectionist that I will be disappointed if the A1c is normal but is higher than last last year's result. Well, if it is, I'll go to work on doing better next year.

Tuesday, September 21, 2010  

I thought it was strange that my after-dinner test wasn't lower than 136, seeing as it was (as far as I could determine) a very low-carb dinner. I had a couple of salmon-burger patties (no bun), and some low-carb vegetables and a tahini dip which was also low in carbs. The ingredients for the salmon burgers included bread-crumbs, but apparently just a few of them, since the listed carb content was 3 grams. I wondered if the labeling was incorrect. I can usually eat a sandwich and still get a post-prandial result under 120, and here I was hitting 136 after a meal with no bread (and on a day which began with a fasting level of 78!). As far as I can see, my meal was mostly protein and fat, with very little carbohydrate. Seemingly it should have had very little impact on blood sugar.

I decided to do a second test at the 2-hour point, and got a 106. Well, that's fine, but I felt as if I should have got it at the 1-hour point.

Oh, well -- this diabetes thing is never really predictable. It may be that a big dose of protein can also raise your blood sugar, although protein seemingly shouldn't have a major impact -- especially at the 1-hour point, as it is digested slowly.

I was toying with a hypothesis that maybe a mainly-protein meal could somehow interfere with the body's handling of whatever carbs the meal included -- but I decided I was speculating wildly, and should just admit that I didn't understand this result.

A dead whale washed up on the beach in San Francisco yesterday, and immediately it was spray-painted with graffiti. Whales may be endangered, but assholes abound.

In many European countries, people are getting fatter and exercising less, and this is showing up in, among other problems, an increasing rate of colon cancer. (Staying in shape apparently has a preventive impact on that disease.)

The European Journal of Cancer reports in its September issue that a study of obesity rates, exercise rates, and colon cancer rates has calculated that, if the populations of other European countries were as fit as the Dutch (who tend to rely on walking and cycling to get around), about 20% of all colon cancer cases in Europe would be prevented.

Weight loss alone, however, is less effective -- and for some reason it benefits women less than it does men. Whichever sex you are, you have to maintain normal weight and exercise to get the full benefit in terms of cancer risk reduction.

No specific mechanism by which obesity or lack of exercise could lead to colon cancer was mentioned in the summary article I read. But lack of exercise seems to be capable of harming us in just about every way we can be harmed, so I guess it's not surprising that increased cancer risk would be among the many penalties of the sedentary life.

Monday, September 20, 2010  

I decided to adjust the color scheme on this site. Hope you like the new look.

All I have to do, to remind myself of the power of exercise, is to take a day off from it. On the morning after my rest day for the week, my fasting test usually goes up at least a little. On other days I can usually keep my fasting result in the 80s, but a day without a workout is all it takes to bump it up to the 90s -- which was the case today. I don't know how much higher my glucose level might climb after several days in a row without exercise, but I'm pretty sure I don't want to find out.

That's why I try hard to avoid having any sports injuries -- I can't afford to be sidelined for an extended period. I've been pretty lucky this year in that regard. I've had very little in the way of aches and pains, even after longish trail-runs, such as this 7.4-miler on Saturday...

But my left hip was a little sore during today's run -- nothing serious, but worrisome just the same. I'll have to watch that, and see what I can do to heal it up. We did some pretty intense hip-stretches in yoga class tonight, and they felt good. My hip felt better after class than it had before. I hope it's better during tomorrow's run. If not, I'll have to figure out something more that I can do about it. Even mild pain is usually a sign that you're doing something wrong, and when I feel sore during a run I try to think of something I could do differently that might help.

A lot of newcomers to diabetes have a mistaken idea about elevated blood sugar: that it has symptoms.

They think they should be able to tell when their blood sugar is high, whether they're testing or not. This assumption often leads them to make other assumptions:

However, the underlying assumption -- that you can tell your blood sugar is high without measuring it -- is almost entirely wrong. Generally speaking, elevated blood sugar has no symptoms. You feel the same at 180 as you do at 90.

Some would disagree with me about that, I realize. People who test regularly often develop a subjective impression that they can "feel" what their next test result is going to be before the numbers appear on the meter's little display. I doubt this. I think it is far more likely that this "feeling" of theirs is really an inuitive calculation of what kind of result is most likely, given the circumstances and given everything that testing has taught them about themselves. (They say that they "feel" high; I think they know they are probably high, given what they ate for lunch -- and it is this knowledge, not their glucose level, that is affecting their feelings.)

When blood sugar is extremely elevated, it does make you feel bad, but not in such a specific way that a doctor could recognize the cause on that basis alone. The fact that you are feeling ill, exhausted, and perhaps dizzy is not a very precise indication what is wrong with you. There are plenty of diseases that could make a non-diabetic person experience those symptoms. There is one exception: over-frequent urination is, I admit, typically a diabetes symptom. Not too many diseases besides diabetes will cause that to happen. But your blood sugar has to be very high, not just above normal, before that symptom appears, and even when it does, it may take a while to get your attention. Not many people keep track of their urinary output so well that, if it increases, they will immediately notice the rising tide, so to speak.

At any rate, your blood sugar can certainly rise high enough to be harmful to you without making you feel any different, or making you visit the bathroom more often. If you want to know what's really going on, you have to test. This is a big enough problem for people who do test their blood sugar (since they can't be testing it all the time, and if there's a big increase between tests they're not going to be aware of it). It's an even bigger problem for people who don't test, especially if they don't yet know they have diabetes.

Developing diabetes is like having a hole open up somewhere in an exterior wall of your house, in a location that isn't easily visible. The hole is letting outside air flow into your home, but you don't know it's there. It didn't matter much during the summer, but as the weather cools down in the autumn, it starts to have an impact on the temperature indoors. However, you're not necessarily going to know about it even then -- because you have central heating, and a thermostat. To keep the place warm despite the hole in the wall, your thermostat has to turn the furnace on more often, to compensate for that draft coming in from outdoors. Your central heating has to work harder to maintain the same temperature than it used to, but so long as it actually does maintain the same temperature,  how are you going to know there's a hole in the wall? The only way you're going to realize what's happening is if you notice that your heating bill is going up for no obvious reason, and you start poking around in the attic looking for leaks. Or, if you just blame the increase in your heating bill on rising energy costs, and ignore the details, you still might not find out, until the weather gets so cold that your thermostat can no longer compensate for the problem. When it starts to be cold in your house even with the furnace on constantly, you'll know that you have either a bad furnace or a leaky house.

That's the way diabetes usually develops. The underlying problem may be there for months (or, more likely, years), but your thermostat, by which I mean your endocrine system, is able to compensate for the problem. For a long time, everything seems normal. Not only do you feel normal -- you probably test normal, too. In the early phases, the problem is very well hidden. And even when the situation gets serious enough that a glucose test could reveal what's going on, it may not get far enough out of control to make you feel any different.

There is something spooky about the way diabetes sneaks so quietly into our lives, and then suddenly is revealed to us. It's like turning around, when you've been busy setting up a tent, to find that a mountain lion has been crouching behind you, watching your every move. It's upsetting enough to be confronted with a predator -- but to know that it was there behind you for who knows how long, while you were looking the wrong way! There are some very deep fears involved in this. Maybe that's why even those of us who are apparently managing diabetes successfully have a very hard time relaxing, enjoying our success, and trusting that we know what we need to know about the situation. We remember that diabetes surprised us once, and we can't shake off the fear that someday it will surprise us again.

But a lot of people err on the other side -- instead of being troubled because they can't tell when their blood sugar is elevated, they become troubled because they assume that they can tell, or should be able to tell, when their blood sugar is elevated. They need to revise their thinking on this; the collision between reality and false assumptions can be a very stressful thing.

Friday, September 17, 2010  

People newly diagnosed with diabetes have so many questions -- and such basic questions -- that it can seem almost breathtaking to those of us who have been dealing with diabetes for a while. It almost gives you flashbacks, to the time when you didn't know about any of this stuff either. Today I saw a posting from a novice diabetes patient who admitted to being unsure if there are "any bad foods". It made me feel like a kid again.

To be more specific, it brought to mind youthful discoveries of complex subjects (such as astronomy and classical music) which, once I got a taste of them, I had to learn all about. But where do you begin? That almost doesn't matter, really, if you're young enough. You choose some arbitrary starting point, and you branch out from there. You start by learning the constellations, and that leads you to binary stars, Venus, meteors, or whatever else catches your interest along the way. You start with Beethoven, which leads you back to those he idolized (such as Mozart) and forward to those who idolized him (such as Schubert). But there's needn't be any system to it, when you're young and curious and hungry to know more. You learn fast, of course, but you're free to learn at your own pace -- it doesn't matter when you get around to learning about the Oort cloud, or Les Troyens, because your life doesn't depend on these things. Both Jupiter and the Jupiter Symphony will still be there waiting for you, whenever you finally take them up.

I wish I could say that you can learn about diabetes at your own pace, because your life doesn't depend on that subject, either. But we all know that this is not the case.

It would be nice if people learned about diabetes before they got it, so that they'd be ready to hit the ground running when the time came, but let's face it: people don't. The average non-diabetic person knows about as much about diabetes as he knows about methods of cathedral construction in medieval France. It's not hard to guess why this is the case, either. Diabetes is an almost absurdly complicated subject. Nobody is going to take the trouble to learn about anything that complex unless they have something at stake personally. Of course, millions of people do have something at stake personally with regard to diabetes, but they don't know it yet. When they finally get the news, that's when they'll start studying up on diabetes. Not a moment sooner.

All this is understandable, but it does make it a bit difficult to know where to begin, when you finally have to start learning about the subject in a desperate hurry. And it doesn't help that there is so much contradiction and controvesy and uncertainty about the nature of the disease. It is true enough to say that more is being discovered about diabetes every day, but the flood of new data coming in does not always lead in the direction of heightened clarity. Every week or two I read about some new gene, enzyme, or protein which is supposedly THE underlying cause of diabetes. Diabetes seems to have more causes than a dog has fleas. Not that diabetes novices tend to delve too deeply into the current research on diabetes fundamentals, but they do seek advice on what they're supposed to do about their diabetes -- and they're likely to be driven nuts trying to figure out whom to believe, when the advice that's available to them is so inconsistent.

It seems to me that there is a need for a short and simple -- but useful -- explanation of Type 2 diabetes, but it's terribly hard to construct one. When people try to do this, they usually come up with something which is short and simple, but is not useful. I've tried to do better myself, without much success.

The physicist Richard Feynman said that, if all scientific knowledge were lost in some cataclysm, and only one short sentence could be passed on to the next generation to help them start science over, his proposed sentence would be this: "All things are made of atoms -- little particles that move around in perpetual motion, attracting each other when they are a little distance apart, but repelling upon being squeezed into one another." I doubt I can think of anything that brief that would be of actual use to someone newly diagnosed with diabetes.

I think this is about the best I can do: "Concentrate mainly on experimenting with your lifestyle, to discover those things which actually drive your blood sugar downward -- and whenever you find one, do more of it".

My reason for choosing that sentence is that I think diabetes novices are usually too passive -- they assume it's all about following some expert's rules, instead of experimenting to find out what works for them. It's nice to find an expert who impresses you, but it's nicer to have some evidence that following that expert's advice is actually making things better for you.

Thursday, September 16, 2010  

I thought I'd be lower than 130 after dinner -- a meal which seemingly was low enough in carbs to give me a result under 120. But nothing about blood glucose is ever fully predictable, no matter how well you know your own patterns.

I had a light lunch, and my dinner was delayed. By the time I ate dinner, I was starting to feel hypoglycemic. I wonder if I dipped too low while I was waiting for dinner, and my system overcorrected for the low before the meal had a chance to do anything about it? That sort of thing can happen.

I realize I'm talking about smaller variations than what most diabetes patients experience, and discussing them as if they were dramatic extremes. That seems to be what happens as you get your blood sugar under better control: your standards become more strict, and a result which you would once have regarded as perfectly fine begins to seem disturbingly off-target.

A lot of diabetes patients, when they're taking a glucose test and waiting for the number to appear on the little screen, have very little idea what the outcome is going to be. They don't feel that they can even predict the result within 50 points, so they're braced for almost anything. As your control improves, though, you may get to the stage where you think you know what the number is going to be -- and you're startled and upset if it's 10 points higher than that. Which, of course, is a bit silly, because the repeatability of glucose meters is mediocre enough that an individual reading could easily be off by that much.

I guess it's the downside of achieving good control: the curse of perfectionism. Fluctuations in your results still bother you just as much as they did before, even though the fluctuations are a lot smaller than they used to be. You get hypersensitive to things that probably don't make much difference.

Still, considering how much concentration it takes to maintain good glycemic control, it's probably better to be frustrated in your perfectionism than to be contented in your indifference.

Funny thing: my blood pressure was lower than I expected (after a stressful day). And my fasting test was good. So not all my test data frustrated me today.

Sometimes two news stories appearing together on the same day seem to comment on each other in a bizarre way. On Medscape today, there was exactly this kind of juxtaposition... 

Johns Hopkins Physician Shot by Distraught Son of Patient
A man described as distraught about the condition and medical treatment of his mother at the East Baltimore (Maryland) campus of Johns Hopkins Hospital shot and wounded a physician there this morning before killing the woman and then himself, according to Baltimore police. The physician was briefing the man about the patient outside her room, police said, when the man became emotionally overwhelmed, pulled out a semiautomatic handgun, and shot the physician once in the upper abdomen. The man then entered the patient's room, where both were discovered dead at roughly 1:30 pm EST, police said. Both had a single gunshot wound to the head.

Can Shooter Video Games Improve Decision Making?
Violent video games may help trigger-happy players make decisions faster in real life, according to a study released on Wednesday.

I am curious to know whether the impulsive hospital gunman was one of those lucky people who've had their ability to make rapid decisions "improved" by playing violent video games.

It was also a big day for News Of The Unsurprising. One study has found that the combination of bipolar disorder and drug abuse increases the risk of violent behavior. Another has found that people who get long-term treatment with opiods for chronic pain often develop addictions to drugs and alcohol, and tend to show up in the emergency room more than other people.

I certainly would have thought that rates of violent crime would be lower rather than higher among manic-depressive drug addicts, but apparently it isn't so. And I would have expected that people suffering chronic pain severe enough to require long-term opioid treatment would be healthier and happier than the rest of us, instead of having all those problems that the study revealed. You never can tell, can you?

Wednesday, September 15, 2010  

It's such a nice day -- let's talk about mortality curves!

If you study a population of humans over time, and plot the increasing percentage of them who have died against the increasing age of the individuals involved, you get a rising curve that looks something like this:

The curve keeps rising until 100% mortality is reached -- and the curve gets mighty steep as the limits of the human lifespan are approached.

However, you only get that single line on the graph if you consider the population as a whole, and include everyone at once. Suppose you split the population in some way, and consider those groups separately, drawing a separate line on the graph for each of them. If all groups have the same mortality rate, then you'll still end up with a single line, for all practical purposes, because the same curve will apply to everybody. For example, if you split the population into people with odd-numbered Social Security numbers and people with even-numbered ones, I doubt you're going to find that one of those two groups dies younger than the other, and therefore I doubt that you'll end up with two distinct curves. If you split the population into rich and poor, however, you might see a significant difference.

To make it a little more obvious, you might split the population into those who do and don't engage in some dangerous activity:

I'm guessing that, if you compare those who drive motorcycles while drunk to those who do not, it will turn out that more of the former are dead by a given age. However, this is no more than a guess on my part. It seems like a reasonable assumption to me, but for all I know I could be quite wrong about that, because I haven't actually carried out the population study that I've just described.

If you want to find out what makes us live longer, and what doesn't, you need to split up a population in this way and see what actually happens to them over time. In other words, you need to do a "cohort study", in which people sharing a given characteristic are compared to people who don't share it. This isn't an easy thing to do, because you have to study an awful lot of people, and you have to track them over an awfully long time, in order to end up with statistically significant data. This sort of thing isn't done every day.

However, it was done recently, in China. I read about it in an article entitled Combined Impact of Lifestyle-Related Factors on Total and Cause-Specific Mortality among Chinese Women.

This is a big study (more than 70,000 women participated), and so far it has followed the women for 9 years. The object of the study was to split the women into "cohorts" based on their lifestlyles. Five specific lifestyle factors were identified (factors which were assumed to be beneficial to health), and the women were given "health scores" depending on how many of these factors were applicable to them. The lifestyle factors were:

The women were split into cohorts based on a health score indicating how many of these criteria they satisfied. If these lifestyle factors were, indeed, beneficial to health, the mortality curve would be more favorable in the women with the higher health scores. And that is exactly what the researchers found:

The higher the health score, the lower the mortality rate. "We found that healthier lifestyle-related factors -- including normal weight, lower WHR, participation in exercise, never being exposed to spousal smoking, and higher daily fruit and vegetable intake -- were significantly and independently associated with lower risk of total and cause-specific mortality. Healthy lifestyle scores, composite measures of these five factors, were significantly associated with decreasing mortality as a number of healthy factors increased. The associations persisted for all women regardless of their baseline comorbidities. Results show that lifestyle factors other than active smoking and alcohol drinking have a major combined impact on mortality on a scale comparable to the effect of smoking as the leading cause of death in most populations."

I guess that settles that.

Now we need to do a cohort study to find out which of these two approaches to sandwich-making is better for you over the long haul:

Tuesday, September 14, 2010  

One of my running buddies at work told me about a pilaf salad recipe (with nuts, basil, bell peppers, and a cooked multi-grain mixture). It looked good to me, but it was obviously high-carb, so I wanted to see if I could get away with eating a sizeable bowl of it for dinner. Did I get away with it? Well, that depends on how you look at it. I met my doctor's target (<150 after 1 hour), so that's nice, as far as it goes. But the target I prefer to aim for these days is a more truly normal <120, and I didn't even come close to meeting that. So, much as I enjoyed the meal, it doesn't look as if pilaf salad should be something I eat very often.

It's too bad that most of the foods I really like are high-carb. Meat I can take or leave -- and I mostly leave it -- but I have a mighty hard time turning aside from cereals, potatoes, and baked goods. No gigantic muffin or oversized bowl of oatmeal ever looked too big to me (at least until I checked my glucose later, and decided that I'd gone too far).

With a one-hour reading as high as 146, I figured I'd better check at the two-hour point to make sure I hadn't stayed high a long time. The result was 94, which is a little more reassuring. Still, I think 120 is the maximum "normal" reading after a meal, so it's best to stay under that if possible. And it clearly is possible for me, if I limit my carbs a bit more than I did tonight.

Today the Corn Refiners Association applied to the federal goverment for permission to refer to High Fructose Corn Syrup on food labels as "Corn Sugar". They claim that the name change will "ease confusion".

Oh dear -- is the term "High Fructose Corn Syrup" confusing people? Funny how it never used to cause confusion, and now, after all these years, confusion reigns.

I think it's far more likely that the real problem with the current name is that it isn't confusing enough. Consumers have found out what it means. And, in increasing numbers, they are choosing not to buy food products which list it as an ingredient. The makers of those products are now starting to avoid use of the stuff, and the result is that, after decades of steady growth, HFCS sales are down. Clearly, something must be done! We can't have consumers making their own decisions about what they will put in their mouths!

The makers of HFCS feel that their product has been unfairly maligned, and blamed for an obesity epidemic which is not their fault. Well, yes and no. Most attempts to identify specific harmful effects of HFCS, as compared to other forms of sugar, have found ambiguous evidence or (more often) none. Although a lot of people with diabetes report that HFCS spikes their blood glucose like nobody's business, those who have studied the metabolic effects of the stuff have usually found that it is no worse and no better than any other kind of sugar.

However, the artificially low cost of HFCS (thanks to government subsidies of more corn than anyone wants to eat) have tempted the processed food industry to use HFCS more and more heavily over the years, sneaking it into almost every food on the grocery store shelves. The result is that our perceptions have gradually altered, and food which isn't heavily sweetened doesn't taste right to us anymore. Even if we eat the same foods we used to eat 20 years ago, our calorie intake is higher now because 20 years ago those foods weren't carrying the same load of hidden sugar that they carry today. (Did you think dried fruit was just dried fruit? Nope -- it's usually drenched in HFCS.) As the annual consumption of HFCS rises higher and higher, how can this flood of added sugar not play a role in the obesity epidemic?

If the consumer revolt against HFCS results in nothing more than HFCS being replaced by some other form of hidden sugar, then it really won't make much difference. But other forms of sugar are more expensive, so maybe the makers of processed foods will learn to be a little less extravagant with the stuff, and bring down the calorie count of their products a little. That at least would be progress.

However, even if consumers are "confused" about HFCS, in the sense that they are wrongly perceiving it to be intrinsically worse than the same amount of sugar in another form, I think it's their right to decide whether or not they want to eat a particular food ingredient. Suppose that consumers decided that they didn't want to buy clothes made of cotton -- for what reason doesn't matter. Maybe they decided that cotton cultivation was especially unfriendly to the environment (I think there are reasons to suppose that it is), or maybe they were buying into somebody's weird hypothesis that exposure to cotton fibers causes autism, or maybe they just decided that cotton is out of fashion, and cool people don't wear it. Regardless of why they don't want to buy clothes made of cotton, they have the right to make that decision if they want to. Therefore, if clothing manufacturers react to this by changing the word "cotton" on clothing lables to Gossypium barbadense, on the grounds that this is the the internationally recognized species name for the cotton plant and will therefore eliminate potential  "confusion", we would all agree that the name-change was intended to hoodwink the public, and had no other purpose.

If the Corn Refiners Association truly wanted to eliminate confusion, they would rename HFCS as "Corn Starch That Has Been Half-Digested For You In A Chemical Treatment Plant". But they wanted a euphemism, and Corn Sugar is the euphemism they settled on.

Euphemisms have a problem, though. Sooner or later, even the most successful euphemism becomes universally understood, and then it ceases to function as a euphemism. Once upon a time, "handicapped" seemed a hundred times nicer than "crippled", but once people got used to the word "handicapped", it took on the same negative connotation as "crippled". So then we needed a euphemism for "handicapped", and along came "disabled". But after a while, people knew what "disabled" meant, too. It's a never-ending difficulty; you have to keep coming up with new euphemisms every five years or so.

So, if "Corn Sugar" becomes accepted, it will later have to be replaced by some term that consumers don't know, such as "Maize Jelly" or "Kernel Ooze".

It's going to be interesting to watch the subequent history of this name-change.

Monday, September 13, 2010  

A reader who who wrote to me anonymously explained why he's using a pseudonym in his communications about diabetes: he was diagnosed recently, and so far only his doctor and his wife know he has the disease. He said that he's still in the closet about his diabetes.

Aside from bringing to mind a joke I heard about 30 years ago ("Why is it easier to be black than gay? You don't have to tell your parents!"), this also brought to mind an issue which I usually ignore, even though I know it affects a lot of people with diabetes. Whom do you tell? Is it safe to tell? Can you get away with not telling? What will happen if you do tell? What will happen if you don't tell, and people find out anyway?

I've never attempted to keep my diabetes a secret from my relatives, friends, or employer. I don't casually announce it to everyone I meet, of course. Many people I work with don't know this about me. I don't tell them unless there is some reason to discuss the subject, and I have time to discuss it in enough detail to make it clear that I have the situation under control and they don't need to worry about me. On the other hand, this site identifies me by my real name, says roughly where I live, and even includes pictures of me, so any curious co-worker who wanted to find out more about me could easily make the discovery. This isn't a secret -- it's just a subject I prefer to discuss with people only when I'm ready to discuss it.

I don't mean to suggest that, because I haven't been secretive about my diabetes diagnosis, other people don't need to be secretive about theirs. Some people may have excellent, practical reasons for trying to keep the issue under wraps. Perhaps their workplace, family, or social circle is very different from mine, and they have good reason to think there would be some kind of undesirable consequences if news of their diabetes diagnosis became too widely known.

For example, my duties at work don't involve operating a crane or a shuttle bus; nobody at the office is going to think that I might introduce an element of danger into the workplace by having a "diabetic reaction" at the wrong time. ("Diabetic reaction" is an extremely vague term which describes whatever people are afraid might someday happen to a person who has diabetes, up to and including lycanthropy.) But some people, because of the nature of their work or the nature of the organization they work for, have reason to worry that their careers will be harmed if people know they have diabetes. Others have reason to worry about family or social consequences if their diabetes becomes common knowledge.

I'm not going to argue with anybody who is trying to keep a diabetes diagnosis quiet because of some specific, realistic concern. However, keeping a diabetes diagnosis a secret can be burdensome, and can even handicap you in managing the disease. Therefore, keeping it a secret is worth it only if you have a specific, realistic concern. People who keep it a secret based on vague and unrealistic concerns may be making things harder on themselves, for no good reason.

If you keep your diabetes a secret only because you don't want people to see you as unhealthy, keep in mind that health is hard to fake. People are going to see you as healthy or unhealthy based mainly on what they see, not on what you tell them or don't tell them. Healthy people look healthy. The clues which tell us who is looking well and who isn't are subtle and hard to define, but few observers miss them. If you're healthy, people know it. If you're not, people know it. Therefore, your best defense against being perceived as unhealthy is to concentrate on making yourself as healthy as you possibly can, rather than to concentrate on hiding your health problems.

One of the reasons I wanted my diagnosis to be known to management at my company is that I wanted to have the flexibility to build a serious workout into my daily schedule. Plenty of people at my workplace, including managers, do that too, and in general it's seen as a good thing. But I wanted to get it established that I'm doing this for a good reason. And that was the right thing to do -- in my situation, anyway -- because, in the years since I started working out at lunch, nobody has ever given me any flak about it. The fact that I am so often seen running in the neighborhood at lunchtime has given me a reputation for good health which more than cancels out any reputation for bad health which I could be getting from having my diabetes diagnosis known. To the extent that people are aware of that diagnosis, they seem to see me not as "the guy who has diabetes" but "as the guy who beat diabetes". Some of them even think of me as the guy who used to have diabetes, or (more bluntly) as the guy who used to think he had diabetes. Sometimes I actually have trouble persuading people that diabetes is a real issue for me, not a hypochondriac fantasy.

But, again, I'm describing the situation where I work, and many people work in a very different kind of situation. It's not for me to tell them that they should be more open about this, when I don't know what challenges they would face if they took me up on it.

And I'll admit that I've been very slow to discuss the subject with one particular set of co-workers: our transplanted Scots. They arrive here, fit and athletic, with the most awful expectations about how fat and unhealthy Americans are going to be, and they think I don't fit that profile. I hate to blow my cover and admit that I used to fit it perfectly. So, I keep quiet about the subject around them. I won't lie to them about it, but I'm not looking forward to chatting about it, either. We all have our limitations, I guess.

We all have our pet peeves, too. Being a writer, I naturally have some pet peeves that are related to writing. One of them is the misuse of scare quotes. Although the term scare quotes is perhaps not universally understood, the practice it describes should be understood by anyone who reads English at all. And yet, and yet... 

Scare quotes are quotation marks which you put around a word or phrase when you are trying to distance yourself from that particular expression, because you disapprove of it or disbelieve it. For example, suppose you were writing about an election in Iran, and you felt that it wasn't a proper election at all, but couldn't avoid using the word. What would you do, to distance yourself from that word and indicate that you weren't using it naively? You would use scare quotes. Instead of writing about an election in Iran, you would write about an "election" in Iran. In conversation, the equivalent of scare-quotes would be to refer to it as a so-called election, or to make that silly gesture in which you draw quote-marks in the air with your fingers, or to roll your eyes and adopt a sarcastic tone.

Now that we all understand the proper use of scare quotes, let us talk about the improper use of scare quotes -- an improper use which drives me up the wall. Some people seem to think you can put an expression in scare quotes not to undermine it, but to emphasize it.

No, no, no! We use italics for emphasis. Or underlining. Or, if you absolutely must, block capitals (but be careful with that one -- two many block capitals are perceived as yelling). But you can't use scare quotes for emphasis! Scare quotes don't add emphasis -- if anything, they subtract it.

Put it this way: potential customers might be pleased to see it stated in writing that your restaurant serves fresh food, but they certainly don't want to see it stated in writing that your restaurant serves "fresh" food. People who don't realize there is a difference between fresh food (good) and "fresh" food (hilariously bad) are not the sort of people who are meant to be retaurateurs. But you see this kind of mistake amazingly often, and not just on menus.

Today I received an e-mail at work which read, in part, as follows:

Save the Date... Thursday, September 23rd!

Please plan on joining us for a Picnic/United Way fund raising event:

Although I'm ready to concede that an event featuring the Management Team might turn out to be a "fun" event rather than a fun event, I'm sure the author of this e-mail wanted me to assume that a "fun" event is even better than a fun event, and I know it isn't. I've been to fun events, and I've been to "fun" events, and I know the difference between them.

Do people really read so little these days that this kind of blunder comes naturally to them? It's hard for me to see how anybody who's got as far as high school could have failed to pick up on a convention as basic as scare quotes. I wonder what else they've failed to pick up on?

Friday, September 10, 2010  

I had almost forgotten about Rooibos tea (the South African herbal tea which is claimed by some to reduce blood sugar), but for the last couple of nights I've had a cup of it at bedtime, and in both cases my fasting test the next morning was unusually low. Which proves nothing, really, but if the tea wasn't what brought those two fasting tests down, at least I know that it didn't drive them up. I think I'll make the Rooibos tea a bedtime routine for a while, and see if there's any persistent trend.

It's pronounced "ROY-bos", by the way. It means red-bush. There's no caffeine in it, but it does contain several compounds that are thought to have a beneficial impact on human health.

I had a hard run today (a very hilly route), and I'm very much looking forward to taking a rest day tomorrow.

For a lot of us, managing diabetes is, at its best, like going out on a beautiful spring morning and taking a walk through a minefield. We look around us, and everything seems fine, but we're nevertheless afraid that some terrible surprise may be lying hidden in our path, waiting for its chance to catch us by surprise and turn our world upside down in an instant. I guess it's because the diabetes diagnosis itself came to us as a sudden, shocking development (the doctor phoned to say that something bad showed up on the lab report). Naturally, we worry about what the next ugly surprise will be, and when we'll find out about it. This anxiety about hidden dangers has a certain quality-of-life impact on us. It's hard to enjoy your success if you're constantly wondering if your success is really just a temporary improvement which will soon vanish -- or an illusion which will soon be shattered.

When I embarked on my diabetes journey -- and specifically on my project to control my diabetes through lifestyle changes rather than prescription drugs -- I was bothered by the often-expressed expert opinion that such an approach can work for a short while, perhaps a few years, before it fails. The most optimistic prediction I ever read was that diabetes could be managed without medication for "up to ten years". But the general consensus seemed to be that Type 2 diabetes inevitably got worse over time, which meant that sooner or later (and probably sooner) everyone with disease would have to take oral meds, and would later have to take insulin, too.

Because of these pessimistic predictions, I have spent the years since then waiting for my lifestyle-based approach to stop working. Whenever I had a setback of any kind, and noticed my blood sugar creeping up, I would think "This is it -- this is where I lose control of my blood sugar, just like they all said I would!". But, instead, I would make the necessary adjustments (more exercise, less starch), and then I would very soon get back on track.

So now I'm getting pretty close to the ten-year cut-off point. In early February, I will be celebrating (if that is the word) the ten-year anniversary of my diabetes diagnosis. It should be a scary prospect, considering that this is when the optimists think I will leave behind any possibility of continued success.

However, even though I have never stopped thinking about this ten-year anniversary, I have become less superstitious about it as it has come nearer. If failure at the ten-year point really were inevitable, I think the signs of imminent failure would be appearing by this point. And instead, I'm capable of pulling off a fasting test below 80 and a post-prandial test below 110. Not that my results are that good all the time, but I think someone who was heading for a serious breakdown of glycemic control within five months would probably be having a little more trouble than this.

Thursday, September 9, 2010  

You know, I really didn't have a proper rest day last weekend (I didn't run on Saturday, but I went on a fairly substantial hike), and I guess I'm starting to feel it. Running wasn't easy for me today. You might even say that I didn't feel like doing it.

Well, it was the latest in a long line of opportunities to remind myself that it doesn't matter what I do or don't feel like doing. It's Thursday, and I run on Thursdays, and that's that. This is not a negotiable issue. (A few years had to go by before I let go of the idea that it was, too, negotiable, but eventually I did let go of it, and life got simpler.)

It turned out to be a beautiful day for a run, though.

I went to an excellent house-concert in the evening: the Scottish fiddler Catherine Fraser (who is actually from Australia), accompanied on piano by Duncan Smith. Here's a video of them in New Zealand playing a set of tunes that they also played tonight. I love house-concerts: the intimacy of the music-making, the beauty of music coming at your ears directly instead of through a loudspeaker, the good behavior of an audience that's in someone's living-room instead of in an auditorium. Let there be more house-concerts!

Unfortunately, it didn't leave me much time for blogging tonight. But here's something...

Looking through the health headlines, I often find that the author of a story (or the editor of the publication in which it appears) has chosen a title for the story which could be paraphrased as "New Study Reports Results So Utterly Predictable That You Needn't Bother Reading This Summary Of Them".  Why they do this I don't know, but they certainly do it a lot. I guess they're trying to discourage widespread reading of their articles.

Today I browsed through the latest list of articles in Medscape, and here are some of the headlines I found there...

Oh, well -- who am I to criticize? Somebody's got to engage in pointless research, or it wouldn't get done!

Wednesday, September 8, 2010  

A very autumnal day, for early September in these parts. It looked as if we were going to get rained on during our lunchtime run -- the clouds were getting very dark and threatening for a while. But it stayed dry. Cool, though. Nothing wrong with that when you're running up steep hills, of course, but there was that summer-is-over sadness in the air, which affects me even though, if I'm honest with myself, I like autumn a lot better than I like summer anyway. 

There is something about the Hemoglobin A1c test, as a subject for discussion, which seems to discourage thought. I am pretty sure that more careless and questionable things have been said about this test than about any other diabetes-related subject.

The reason for this, as far as I can make out, is that the A1c test is almost always seen in purely symbolic terms. People don't think about what the test is, or what it actually measures. They think about what it supposedly stands for. Consequently, their comments on the subject tend to be emotional, political, and even hysterical. They give you the impression that, if they ever did understand the purpose of the test, they've forgotten this information. They are much too busy reacting to what they think the test means to devote any thought to what the test is.

A particularly striking example of what I mean is provided by this Medscape article entitled Diagnosing Diabetes With HbA1c Leads to Racial Disparities :

Efforts to adopt a more accurate test for diagnosing diabetes may have hit a snag. Comparing the oral glucose tolerance test to the hemoglobin (Hb)A1c test confirms earlier evidence that race may influence test results, Danish researchers report. Also, HbA1c will likely identify more people, especially ethnic minorities, as diabetic, which "will have substantial consequences for the healthcare system in terms of diabetes treatment and management," the authors note. "The prevalence of diabetes differed considerably according to diagnostic method," they write in their paper, published online August 25th in the Journal of Clinical Endocrinology and Metabolism.

You see, there is growing evidence that people of different ethnic backgrounds get different A1c results -- even when they get similar results in glucose testing. Non-white patients tend to score higher on A1c tests than white patients with comparable glucose test results. The article continues:

Dr. Anthony J. Bleyer of Wake Forest University in Winston-Salem, North Carolina, who was not involved in this study, told Reuters Health that "the effects of race on a patient's results won't make much difference in that patient's care, but it could make a big difference when that patient goes to buy life insurance if a certain cutoff is used to diagnose diabetes."

"African Americans are more likely to be diagnosed with diabetes if this (difference) is not taken into account," he said.

"Each doctor and patient wants the test to be accurate, correct? Why should we tolerate it to be just a little bit inaccurate in African Americans," he asked.

So you can see the assumptions that are being made here. If some ethnic groups are getting higher A1c test results than other groups with similar glucose test results, this must mean that the A1c test is wrong. It couldn't mean that the glucose test is wrong. Also, it couldn't mean that the A1c test is accurately measuring something which, for reasons unknown, actually does vary between different ethnic populations. (Why couldn't it mean either of those things? Well, it just couldn't, that's all!)

But let's put aside all these concerns about life insurance and racial politics for a moment, and think about what the A1c test actually measures. It measures glycated (that is, sugar-coated) hemoglobin. It takes a look at your blood, and determines how much of the hemoglobin in your red blood cells has acquired an unwanted encrustation of glucose. The test is often recklessly described as measuring "average blood sugar", but it doesn't measure that, any more than a bathroom scale measures calories. It just so happens that rising blood sugar tends to increase the "glycation rate" -- that is, it tends to increase the rate at which blood-borne glucose bonds itself to proteins. Working backwards from the test result gives us a basis for guessing, fairly accurately, what your average blood sugar has been lately. Still, the main reason we care about (or at least should care about) the A1c test result is that it measures glycation, and glycation leads to diabetic complications, and we want to prevent those.

The other reason that we should care about the A1c result is that it is able to catch what glucose testing often misses -- an overall trend toward elevated glucose, even in people whose glucose is not elevated all the time. Diabetes often goes undetected for years, simply because a patient's glucose isn't elevated, or isn't elevated enough, during those crucial moments when blood samples are taken for an annual physical. Their glucose might be extremely elevated in the middle of the night, when nobody is testing their glucose -- and in that case, only the A1c test is going to catch it.

It is precisely because glucose testing captures a potentially misleading snapshot of where the patient's glucose level was, on one particular morning, that doctors have been seeking a diagnostic test which is less likely to be fooled by meaningless short-term fluctuations. It should come as no surprise that the A1c test finds more people to be diabetic than glucose testing does -- that, after all, is the point. If the A1c test didn't find more diabetes than glucose testing did, why would anyone bother using it as a diagnostic tool?

If we are going to reject the A1c, as a diagnostic tool, on the grounds that it finds more "hidden" diabetes in non-white patients than in white patients, we can't do this simply on the basis of a knee-jerk assumption that the A1c test is being unfair to racial minorities -- that it "accuses" them of being diabetic when they're not.

Before we go there, we must first answer an important question: exactly why does the A1c test find more hidden diabetes in nonwhites? Maybe the test is somehow overstating the amount of glycated hemoglobin in the blood of nonwhite patients, but if so, how exactly is that happening? No one seems to have proposed a mechanism which would account for it, and it's hard to imagine one. The fact that it's hard to imagine one does not rule out the possibility of there being one, of course. But other possibilities exist. One is that glycation rates, at the same level of blood glucose, are higher in some ethnic populations than others. Another possibility is that elevated glucose in the middle of the night (when it usually escapes testing) is more common in some ethnic populations than in others.

If it can be shown that higher glycation rates don't matter as much in nonwhites -- that is, if it can be shown that the higher A1c scores in nonwhite patients do not correlate with any increase in the rate of diabetic complications -- then, maybe, we can say that the A1c test gives misleading results for nonwhite patients and should be discounted for that reason. But if it doesn't work that way -- if it turns out that glycation is equally harmful to everyone, but it happens at a disproportionate rate in nonwhite patients -- then it's nature, not the A1c test, that is being unfair here.

I don't pretend to know the actual reason for the racial disparity that is being reported, but I think it would be stupid to assume that it's some kind of meaningless systemic error which we should ignore. (Especially when studies are also showing that nonwhite diabetes patients tend to have more diabetic complications -- which is hardly what you'd expect in the case of people who'd been mistakenly diagnosed with diabetes!) Whether or not the disparity in A1c results reflects a genuine disparity in glycation rates, something is going on here that is more important than the politics of race or the politics of health insurance, and we need to find out what it is. 

The realities of nature are more important, and usually more interesting, than any society's emotional reactions to them.

Tuesday, September 7, 2010  

Most of us have absorbed a number of dubious ideas about nutrition over the years -- if "ideas" is the right word for them. Perhaps it would be more honest to call them sentiments. We have long-cherished feelings about the wholesomeness or otherwise of certain foods, and it normally wouldn't occur to us to research the matter to see if these feelings are justified.  Sentiments, after all, don't require proof.

As an example of this phenomenon, I offer a sentiment of my own: my persistent feeling that honey is more healthful than sugar. I see sugar as a mere vehicle for delivering "empty calories" to the body, but honey is different, at least in my imagination. I tend to think of honey as a health food, if not quite a medication. I suspect that other people must feel the same way, because when sweet processed foods are being marketed as healthy or natural, much is made of the fact that they are sweetened with honey rather than sugar. In a Whole Foods store, I once looked through a rack of organic, whole-grain, nature's-healthful-bounty kinds of breads (baked by enchanted forest animals, if the artwork on the bags was to be believed), and I discovered from the nutritional labels that most of these breads were extraordinarily high in carbohydrate, and even in "sugar" -- and even so, I felt instinctively that this was all right, because the sugar was in the form of honey. And what could be wrong with honey?

Of course, honey is sugar. I know that. But knowing that doesn't change my feelings on the subject. I cannot seem to shake the feeling that honey and sugar are the healthy and unhealthy sides of the same coin.

Why do I react this way? I think it is because honey calls up benign associations in my mind. When I think of honey, I think of beekeeping. I think of monks and other gentle eccentrics, practicing an ancient craft that involves the barest minimum of technology (nature does almost all the work). People don't think of honey as an industrial product; it has so much old-world mystique hanging over it that it can seem cozy and warm even to someone who despises technology. The Oxford linguist and fantasy author J.R.R. Tolkien, perhaps the most committed anti-modernist of the 20th century, the man who resented not only the industrial revolution but the Norman Conquest to boot, saw no reason why he shouldn't cast a romantic aura over honey and honey-making in his stories. (When he wants to let us know just how good the magical elvish bread lembas is, he does so by saying that it is even better than "the honey-cakes of the Beornings". So you can see how good it must be.)

My mental associations with "sugar" are not nearly so charming. From my school days I remember a field trip to a sugar refinery, where the factory environment struck me as ugly, loud, and unsafe. I also remember a Carribean sugar-cane plantation I visited once on vacation, where I heard grim stories about the days of slave labor (and slave rebellions, always brutally suppressed) in the cane fields. With such images in my mind, my instinctive reaction is to feel that sugar is an unhealthy industrial product, but honey is a benevolent natural product. The fact that table sugar is a colorless grit, while honey resembles melted gold, reinforces these feelings.

None of this is pertinent to nutrition, however. What matters nutritionally is what kind of molecules are involved, not what kind of mental imagery. From this point of view, honey is sugar (specifically fructose, glucose, and trace amounts of other sugars). Molasses is sugar too. So is "dextrose". Sugar travels under a lot of names, so that the ingredients list on a food label can include a lot of things that don't sound as if they're sugar, but are. Some of sugar's pseudonyms seem deliberately designed to make it sound more "natural', especially in the case of sugars that are very much industrial products. For example, the ubiquitous "high-fructose corn syrup", so beloved of the processed-food industry, sounds as if it must be some innocent part of nature's bounty, but until comparatively recently it didn't even exist. This product is created through heavy-duty chemical manipulation of cornstarch; there's nothing remotely natural about it. Anyway, sentimental associations with one form of sugar or another can only mislead us. Whatever you call it, it's all sugar, and that's that.

Even starch is really sugar -- or at least it breaks down into sugar soon after you swallow it. Bread, pasta, rice, potatoes, corn -- properly considered, it's all sugar. (Wood is sugar, too, but it doesn't count, because unless you're a termite you can't digest it.)

Of course, persons and corporations with an axe to grind will insist that all sugars are not created equal. Fructose, for example, is the form of sugar we find in fruit nectar, and everyone knows that fruit is good for you, so fructose must be healthier than other sugars. Or, if it isn't, at least we know that different sugars have different molecular structures, and therefore some are bound to be better for you than others. Isn't that right?

No, not particularly. Different kinds of sugar molecules do have different structures, and this remains true right up until the moment you swallow them. After that, however, the differences soon vanish. All sugars, once ingested, are converted by the digestive process into the same molecule, known as glucose, and then it no longer matters whether the stuff originally went into your mouth as fructose (in honey or fruit juice), as sucrose (in cane sugar), as lactose (in milk), as starch (in bread or pasta or rice), or as any other variety of carbohydrate you care to name. Whatever it was when you brought it home from the store, it's all glucose now.

This transformation doesn't take very long, either. Swallow some glucose (which doesn't require any conversion, obviously) and your BG will rise to a peak in something like 20 minutes. Other sugars take only slightly longer. Even "complex carbohydrates" (such as the starch in bread or cereal) only take about an hour. The bottom line is that all sugars, and indeed all digestible carbohydrates, enter your bloodstream as glucose, and they do this very soon after you swallow them.

My purpose in bringing all this up is not to attack honey, or sugar, or anything else. I am simply pointing out how easy it is to develop nonsensical feelings about nutrition. My irrational feeling about honey is by no means the only personal example I could cite. Don't get me started on the health benefits which, in my imagination, can be obtained from hot steak-and-kidney pie served on a cold winter day. I don't know where I picked up this notion; as a lifelong California resident, my knowledge of cold winter days (or meat pies, for that matter) is far from comprehensive. Nevertheless, if you took me to North Dakota in January for a day of ice-fishing, and then invited me into your kitchen and served me a steaming pie stuffed with the more dubious components of a former cow, I would be convinced that this was the best thing in the world for me under the circumstances.

If you closely examine your own feelings about food, I think you might find that some of yours don't bear looking into very well, either. Perhaps you don't share my delusion about honey being healthier than sugar, but you probably have a few delusions of your own. If delusion seems too harsh a word, think of it as shorthand for "unexamined assumption based on emotion rather than evidence". Perhaps you buy into the widespread belief that protein is always good for you, even in massive amounts. Perhaps you think that any fat-free food is automatically good for you. Perhaps you think that any low-carb food is automatically good for you. Perhaps you have the feeling that certain fruits or vegetables or herbs have magical healing properties.

These are all sentiments, not scientific principles. Whatever feelings you have about nutrition, be aware that they can mislead you, and that you must learn to question them.

Monday, September 6, 2010  

Coming up with a real blog would be too much effort for Labor Day. Instead, here's my three-day weekend, summed up in three pictures.

I hope you spent your weekend doing the things you like, too.

Friday, September 3, 2010  

Because of all the running I do, I decided some years ago that I ought to buy an ID necklace -- a kind of dog-tag -- which a lot of runners wear. When you're out running, you're not carrying your wallet, or even your driver's license, and if something should happen to you while you're out there -- passing out, or getting hit by a car, or some such calamity -- you want to be identifiable.

It's not specifically a medic-alert tag, but you can add medical information to it. In fact, you're supposed to add your doctor's name and phone number to the thing. I did put that information on mine when I ordered it. I also had to decide what, if anything, I should say on it regarding diabetes.

I had a vague feeling that I shouldn't leave the subject unmentioned. At the same time, I wasn't sure what I wanted anyone who found my limp body to do with the information. I certainly didn't want anyone to be giving me insulin or metformin on the assumption that I must need them. I came up with a compromise solution which now seems a bit silly to me. My tag reads "HISTORY OF DIABETES T2".

Exactly what I was hoping to accomplish by hanging this message around my neck is a little hard for me to reconstruct at this point, but I guess what I wanted the emergency room staff to think was "Diabetes is some kind of issue in this guy's life, so let's keep an eye on his blood sugar, but let's not over-react, since he only says he has a history of diabetes". I'm not sure that people in emergency rooms actually think that deeply about what's written on medic alert tags. (In fact, two emergency room people I've spoken told me with a laugh that they never even look at those things. There's food for thought!)

Well, it's time for me to order another one, because I've noticed that the etched letters on my dog-tag are starting to fade (probably from years of exposure to the minerals in my sweat when I was out running). Therefore, I need to decide whether or not to mention the D-word on the new one. And I'm having hard time thinking of any reason why I need to mention it.

If I wind up in the hospital in an unconscious state, and my doctor's contact information is on the tag, that really ought to be enough. There's not going to be anything significant going on with my blood sugar, over the short interval before they are able to gather my medical information from my doctor. If I'm going to be in a coma for a while, I guess somebody needs to know about my tendency to become hyperglycemic if I don't exercise -- simply because, if I'm in a coma, I'm not going to be exercising. But that's a long-term issue, not an emergency-room issue. I certainly hope I'm never in a coma long enough for glycemic control to become an issue. But if that happens, giving them enough information to be able to reach my doctor ought to be good enough.

I'm not claiming this is the right approach for everyone with diabetes. Anybody who really needs insulin, or other medications, to keep from getting into serious trouble needs to make sure that people in the emergency room have a chance to find out about it. But this is not an issue for me, at least so far, so I think putting the word "diabetes" on my tag at all will only encourage people to over-react. There's no point in doing that.

But, regardless of what kind of information I have hanging around my neck, I still want to make every effort to ensure that I don't pass out, get hit by a car, or suffer any other calamity while running which will make it necessary for anyone at the emergency room to squint at my dog-tag and say "What the hell did he mean by that?". 

Thursday, September 2, 2010  

I'm going to go a little schizophrenic here, and present both my sympathetic reaction and my unsympathetic reaction to the same issue. I feel both reactions simultaneously, but for the sake of clarity I will discuss one after the other.

First: unsympathetic. 

What's up with these people who are looking for motivation? I mean the people who know what they need to do to get their blood sugar under control, but can't quite convince themselves to do it -- because, they say, they haven't yet found their motivation. What are they, method actors -- paralyzed until they find their motivation? They're sure looking hard for it, though. They know it's out there somewhere, and apparently they'll know it when they see it, but they haven't come across it yet. Sometimes they ask for help in tracking it down, just in case the rest of us have spotted it, running around in the wild someplace.

Probably they they think somebody must have thought of a better motivation than "I don't want to die", and might be willing to share the secret with them. Sorry, folks, but there is no secret. When it comes to motivations, "I don't want to die" is pretty much the gold standard. It doesn't get any better than that. If wanting to avoid getting sick and dying isn't a good enough reason for you to behave yourself, nobody's going to be able to present you with a more compelling suggestion.

Second: sympathetic.

My unsympathetic reaction above might be a reasonable summary of the situation, if the survival instinct were the only instinct that humans must manage. It is not.

For sound evolutionary reasons, humans (like other animals) have a strong inborn urge to preserve their own lives, and sometimes we find ourselves in situations so clear-cut that survival is the only consideration. As I believe Raymond Chandler put it, when a man has a gun in his hand, you are supposed to do what he says.

But most of life does not consist of clear-cut situations in which survival is the only consideration, and the urge to survive is not the only urge that nature has given us. For equally sound evolutionary reasons, human beings have urges which are unrelated to personal survival but might benefit the survival of the species as a whole. Sometimes nature wants us to play it safe, and sometimes nature wants us to pursue pleasure with reckless abandon. For this reason, urging people to play it safe, at a heavy cost to their personal comfort and pleasure, puts you in the same hopeless position as World War II propagandists trying to persuade men stationed away from home to give up sex for the duration of the war.

I think it's unlikely that "You can't beat the Axis if you get VD" really proved to be so powerful an argument that it caused millions of servicemen to banish all erotic thoughts from their minds until late 1945. People aren't wired that way. They want what they want. Even if it's just a piece of pizza, they want what they want. Therefore, it isn't practical to assume that, once we make it clear what the sensible choice is in the long run, everyone will make that sensible choice, ignoring all urges to do something that seems a hundred times more rewarding in the short run.

People need a short-term motivation, in other words. Long term motivations are okay when it comes to deciding that you're going to stop eating pizza, but not very useful when you are trying to think of a reason why you shouldn't eat this one piece of pizza that's sitting right in front of you at this very moment -- a piece of pizza which, as you so sagely remind yourself, is not going to kill you, at least not today.

I've discussed before (scroll down to my blog of August 10, 2010) how I have motivated myself, but this sort of thing is very individual, and I don't expect that others can literally borrow my ideas on the subject for their own use. I only know that people need to find a way to get some kind of immediate satisfaction out of doing the right thing -- and that this is a problem many people find terribly difficult to solve. When people say they're trying to find their motivation, I think this is the issue they're struggling with. They hope someone else can help them with it. They may have to let go of that hope, though. We all need to find our own solutions to this one. 

Wednesday, September 1, 2010  

I was reading a medical article which used the term "SNP" without explanation, so I had to go look that one up. It is pronounced "snip", but it's an acronym for Single-Nucleotide Polymorphism. Perhaps you're thinking that this explanation doesn't get us much closer to a clear understanding of the subject. Well, you have to start somewhere. Let me see if I can explain it further.

Polymorphism means "existing in more than one form", and a nucleotide is one of those four possible "letter" codes stuck to a DNA strand. Actually, they are the molecules adenine, thymine, cytosine, and guanine, but they're usually represented by the letters A, T, C, and G, and are regarded by geneticists as being equivalent to the dots and dashes of Morse code. A long enough sequence of these nucleotides (CAGGCTTACAAACTGTATT... and so on) can be decoded to make a protein, and proteins are what we're made of. Obviously, a code-based system like this works only so long as you don't accidentally change any of the letters. An SNP is a nucleotide which is sometimes replaced by the "wrong" nucleotide-- for example, a "T" instead of a "C", in the example below.

Because a "C" always plugs into a "G", and a "T" always plugs into an "A", you can't really change one letter without changing the one it attaches to, on the other side of the strand. But the important thing about the SNP is that the one of the "rungs" on the DNA "ladder" is C/G in one person and T/A in another person. The two variants of the SNP are called the "alleles" -- usually there is a commonplace and "normal" allele, and an uncommon allele which some people inherit. And this can have consequences.

Somewhat surprisingly, it doesn't always have consequences. Often it doesn't matter which allele you have, because a particular SNP turns out not to have an impact, regardless of which allele you inherit. Either the SNP occurs in a stretch of "junk" DNA which doesn't code for a protein, or the protein it does code for manages to get created in a workable form regardless of which allele you have.

Actually, it's not that surprising that a lot of SNPs are harmless. An SNP that doesn't hurt you is not subject to evolutionary pressure, so it can hang around forever. An SNP that kills you, on the other hand, is less likely to be passed down through the generations, at least if it kills you before you're old enough to reproduce.

However, an SNP (or a particular combination of SNPs) can cause serious problems. Suppose you have a particuar set of SNPs which causes your body to produce a defective form of a hemoglobin. Result: sickle-cell anemia. Or, suppose your SNPs cause a defect in one of the body's cancer-fighting mechanisms. Result: if a cell turns cancerous, the mechanism which is supposed to kill off the cancer cell and keep it from spreading won't work. You would think that SNPs which do serious harm would be eliminated from the gene pool over the years, but there can be interesting circumstances which cause them to persist. The SNP for sickle cell anemia, for example, only kills you if you inherited it from both parents -- and having inherited it from just one parent is actually advantageous, at least in tropical countries, because it confers immunity to malaria. If there were no malaria, the SNP for sickle-cell anemia would have been weeded out, but the malarial-immunity advantage tends to keep it going.

There are quite a few SNPs in the human genome, and scientists have only begun the work of identifying them all, and figuring out the effects that they have, alone or in combination with other SNPs. But it's fairly safe to say that when a particular trait, or a particular disease, is observed to "run in families", it means that those traits or diseases are probably linked to particular SNPs which people in particular families tend to carry. And researchers trying to learn more about particular health problems are often hunting for SNPs that are especially common in people who have that problem.

Whew! I'm almost sorry I started this...

Anyway, what started me down this path was this interesting article about a study which looked at people with some combination of a set of 12 SNPs which are associated with obesity. The goal of the study was not just to confirm that people with more of these SNPs are fatter than people with fewer of them (though it did confirm that), but also to see if physical activity could counteract the impact of the SNPs (it confirmed that, too). The conclusion: "Our study shows that living a physically active lifestyle is associated with a 40% reduction in the genetic predisposition to common obesity, as estimated by the number of risk alleles carried for any of the 12 [SNPs]."

In other words: genetics doesn't have to be destiny. The fact that your SNPs increase your risk of having a particular health problem doesn't necessarily mean there is nothing you can do about it.

These findings about exercise and weight-gain seem to square with my own experience. As a method of losing weight, exercise tends to be a disappointment -- but as a means of counteracting an inborn tendency to gain weight, exercise can be a big help. Follow-up studies on people who lose a lot of weight have tended to show that sedentary people are much likelier than active people to gain it all back.

I think people are in too much of a hurry to declare that this or that health problem is "genetic", by which they mean "it's not my fault, and there's absolutely nothing I can do about it, so get off my back already!". There's a genetic element in everything that happens to our health; sometimes the genetic element plays a powerful and inesecapable role (as in the case of sickle-cell anemia, or Huntington's disease), but often there are things we can do that will actually make a difference.

It's important to draw a distinction between SNPs that you can't do anything about and SNPs that you can do something about. The fact that there are SNPs which give us an inborn tendency to gain weight, or an inborn tendency to become diabetic (some SNPs appear to do both), does not mean that we're doomed anyway, so it doesn't matter how we live our lives.

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