Thursday, September 13, 2007

Fatty Fatty Two-By-Four, Can't Get Through The Kitchen Door

I'm glad to see that Paul Campos has made it big time, publishing in The New Republic on the effects of obesity on mortality rates. Campos is a law prof at Colorado, and also publishes a weeklyish column in the Rocky Mountain News, where he holds court on various topics. But his hobby horse is certainly the topic of obesity, he is author of a book I keep meaning to check out, The Obesity Myth.

I think I've written about this topic before, so I'm not going to go into too many details here. You can read Campos' column if you want the good stuff. But, in short, he writes a lot about how there is significant epidemiological research, most typically meta-studies, which indicate that the healthiest weight category to be in is actually the low end of the 'overweight' range, where overweight is defined as a Body Mass Index (BMI) of 25 to 30. Here, 'healthiest' refers to subjects like life expectancy and health outcomes with respect to various diseases.

There are some counterarguments, the most common two being that these studies are only one of many, and most indicate that having a BMI of around 20 is healthier, and that these studies failed to control for cancer patients and smokers, who tend to be skinnier, but also less healthy.

Campos claims that both of those arguments are debunked. I don't really know one way or the other, and don't have the time or interest to go in-depth enough to find out. I tend to find his arguments convincing, but they are certainly provocative either way.

But it brings up a more general point, which I try and apply every time I read anything about new health studies which reveal some radical new way we should try and live our lives. Mostly, these sorts of questions are very complicated, and you need to bring a good amount of skepticism to any claim that you read or hear about. Even when it's backed up by good epidemiological studies, science is only as good as the controls in place, and the scientists doing the interpretation.

The human body is a phenomenally complicated organism, and it simply isn't a linear sort of device (cut saturated fat by 10%, cut chance of heart attack by 10%, etc.) Most importantly, I think, is the fact, which I think is slowly starting to be appreciated, that our bodies don't all operate the same way. Different people respond differently to all sorts of things; diet, exercise, medicines, etc.

On some level we all understand this; we all know someone who is sensitive to codeine, or penecillin, or who can eat at McDonalds 5 times a week and never exercises but stays a size 2. So I think it's really important to understand that, even if a study shows a statistical signifigance to some effect or other, whatever solution it implies is right (eat more garlic, eat more fish, eat less green beans, whatever) may or may not be right for you.

Which is why I try, however, I can, to adopt a moderate approach to health. We know the following things are good for you: fresh fruits, vegetables, sunshine, puppies, exercise, reasonable quantities of meat, fish, low-fat dairy. Get decent amounts of these things. We know these things are bad for you: twinkies, deep-fried anything (especially deep-fried twinkies), cats, tobacco, lead-coated Hot Wheels. Please try and moderate the amounts of these things that you are exposed to, although total elimination is not expected.

This might not be the ideal solution for you - for you, maybe drinking 3 glasses of wine every day and eating 8 pounds of steak a week might give you the longest life span. But my point is, we just don't know what exactly works for you without running the experiment, and by the time we find out the results, it's a bit late to actually help you.

1 comment:

Michelle said...

Meta-studies my a**. Those suck. And I'm not just saying that b/c a meta-analysis caused my company's stock to tank in May.