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Dizzying Diet News

by Howard Fienberg
December 19, 2002

Almost every day brings a new study on the human diet. Most of them contradict each other (for the last time, does fiber prevent colon cancer or not?!), leaving readers perplexed about what and how much they should be eating.

For instance, as many as 60 percent of 12-year olds and 95 percent of 18-year olds in westernized societies suffer from acne. Recent research from the December Archives of Dermatology indicated that highly processed breads, cakes and cereals are the cause of it. Study leader Loren Cordain contends that the western diet of refined sugar seems to increase the level of insulin produced by the pancreas and some evidence suggests a link between increased insulin levels and acne. There may be some credence to this conclusion, since acne is unknown in isolated subsistence societies who lack access to refined sugars.

But this doesn’t mean your kids have to give up white bread and blueberry muffins just yet. Numerous studies in the seventies and eighties found no link between diet and acne. Denizens of less-westernized societies may be getting more exercise or more beneficial sun exposure. Aside from a lot of old wives tales, there is not much data to go on. That is why Neil Mann, a nutritionist at Australia’s RMIT University, is planning what he calls the first controlled study, putting teenagers on a diet restricting simple carbohydrates. Expect to see his results in 2003, at the earliest.

Wondering if obesity is really the problem anyhow? A recent study from the Annals of Epidemiology concluded you need to worry a lot more about exercise. Consistently, physical inactivity was a better predictor of all-cause mortality than being overweight or obese, said lead author Carlos J. Crespo. After controlling for other risk factors, like hypertension and smoking, Crespo found that growing fat on the couch is not as daunting a prospect as never leaving the couch. The benefit may derive from the fact that regular moderate physical activity, no matter how much you weigh, appears to stimulate the immune system, improve insulin sensitivity and increase bone density, among other positive effects.

Tell that to U.S. soldiers. According to the November issue of the American Journal of Medicine, almost 54 percent of them over age 20 are too fat to fight. As pointed out by Iain Murray, Director of Research at the Statistical Assessment Service (and a TCS contributor), this isn’t because they’re all trench potatoes, but because the military tried to use the silly federal guideline from 1998 marking a person as overweight if they have a body mass index (BMI) greater than 25. Since the BMI is not correlated to increased risk of weight-related diseases until a person measures 27 or more, the military has its own, older standards, using that as the starting point for categorizing personnel as overweight. Using the old BMI standards marks only about 20 percent of the troops as overweight still not a great situation, but given how many push paper rather than haul M16s, it is not so frightening.

Of course, the BMI does not explain as much as you might think. How else could such porkers as Michael Jordan, Arnold Schwarzenegger and Shaquille ONeill all have BMIs targeting them as overweight? Perhaps the Department of Defense should do a bit more research before it puts healthy people on crash diet plans.

Speaking of crash dieting, the December issue of Metabolism put a special vegetarian diet to the test. It found that a diet composed of a variety of foods each known to be moderately effective in combating cholesterol levels, can cut bad cholesterol by close to 30 per cent. According to the study’s lead researcher, that’s not too different from taking a statin drug to lower cholesterol. So should we score a victory against the creeping profit margins of the pharmaceutical firms?

Not just yet. According to the Canadian Press (Dec. 2), A typical breakfast might include soy milk, oat bran cereal topped with chopped fruit and almonds and oatmeal bread with vegetable margarine and jam. Lunch might be soy cold cuts, oat bran bread, bean soup and fruit. Dinner might be stir-fried vegetables with tofu, fruit and almonds. Still interested? Aside from being too small a test to really judge the results of the diet, it seems that it doesn’t exactly help dieters get in shape. All the participants struggled to keep from gaining weight. The study’s author, Dr. David Jenkins, cheerily explains that some of the participants took to the diet like ducks into water some being only 4 out of 13. Those 4 carried on with the diet when the study was finished. The rest were more than pleased to be rid of it.

Jenkins’ previous claim to fame was reporting that if people ate like cave men they would no longer have trouble with their cholesterol levels. However, the amount of food required would turn eating into an all-day activity. You’ll pardon me if I prefer a Big Mac. 


See the original: http://www.tcsdaily.com/article.aspx?id=121902B

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