Tuesday, June 14, 2005

The Gene Hunters

In the July Issue of the MIT Enterprise Technology Review, an interesting article, "Wired to Eat," explores the theory that body weight is determined by genetics.

I'll warn you in advance, the article is long - but it is worth the read!

And, of course, here's the cliff note's version...

Researchers from Rockefeller University in New York have been studying the residents of the tiny island, Kosrae, since 1994. The research team chose Kosrae for its isolation, and because most of its people are descended from just a few families. Since the end of WWII, the residents of this island have gone from being mostly trim and fit, to mostly out-of-shape and overweight/obese.

What's also changed significantly are their eating habits and lifestyle. Before the US took over the island, the residents ate fish, bananas, coconut and taro. In the years since the US started shipping in canned and processed foods, the islanders have gained weight.

The Rockefeller team suspects that the proclivity of a person's body to approach a certain weight is determined far more by genes than was previously thought--specifically, genes that control the impulse to eat. Growing evidence indicates that an individual's weight is 40 to 70 percent decided by genes, which makes it about as heritable as height.

Not everyone agrees though - "There are too many cases where people have willed themselves to lose substantial amounts of weight and keep it off," says nutrition expert Marion Nestle of New York University. Teasing out which perspective is right--or whether, as seems likely, obesity is a complex interaction of both genetics and lifestyle--will help determine our attitudes not only toward fat people but toward the effectiveness of dieting.

On Kosrae...
  • 88% of adults are overweight or obese
  • 50% of adults are obese
  • Diabetes afflicts 1 in 8 adults

Are many of the islanders genetically predisposed to large appetites, which, once food was plentiful, they were suddenly able to satisfy? Or as New York University's Marion Nestle and Kosrae health officials maintain, is it simply a case of a population's sudden shift to an unhealthy lifestyle, which might be corrected by cutting down on frosted flakes and Spam?

The "blame the genes" hypothesis flies in the face of arguments mounted by nutritionists and the diet industry, and of the popular belief that eating habits can be controlled through willpower. "We have some control over eating from our reasoning centers of our brain," says the lead researcher Friedman, "but this seldom overrides our basic instinct to eat when we're hungry."

Friedman contends that exercise and better eating will make Kosraeans healthier but probably will not solve the obesity problem.

What really intrigues Friedman is why everyone doesn't get chubby when there is plenty to eat. Analyses show that the number of lean people has remained steady for the past 30 years, he says. "One's size is not an environmental effect. Nor is it a matter of willpower."

Friedman acknowledges that what he suggests is counterintuitive, since people can resist jelly beans up to a point. But he insists that, for the majority of the obese, free will in weight control is an illusion.

I think it's safe to say that both genetics and lifestyle play a role. We didn't suvive evolutionary forces because we were dieting - we ate when food was plentiful, stored body fat, and survived during lean times and even famines because we had body fat to get us through. Today, especially in the United States, food is available in abundance - and not just good food, but any food, including nutritionally-void, empty calorie foods.

Genetically we're pre-programmed for survival. Our bodies work to primarily ensure our survival and does this on a very primal level - we don't think about it. Over the years as our understanding of food and nutrients has grown, so has our ability to mass produce food. The more we move away from our traditional diet, the fatter we get.

The islanders of Kosrae are living proof of this - by abandoning their traditional diet and adopting one littered with processed foods, they've grown fat. They are not the only population in the world where this is evident - in fact, every population that has abandon their traditional diet for one heavy with processed foods gets fat - the Canadian Inuit, the Pima Indians, or Japanese moving to the United States and adopting the Standard American Diet (SAD).

I don't think we need to spend millions studying the genetics of this phemomenon.

Honestly, what's the purpose of such study? Is it to develop drugs to shut-off genes so we can eat unhealthy foods and not suffer the weight-consequences? Is it to coddle those who continue to eat unhealthy foods, to somehow assure them it's not their fault and give them peace-of-mind as they eat another donut?

How about this - how about we be honest - eating the wrong foods makes you fat, leaves you malnourished, increases your hunger as the body tries in vein to get the nutrients it does need, and causes your body to revolt with the emergence of disease and degeneration. It is a vicious cycle that you can stop.

Make the commitment to your health and well-being...stop eating the wrong foods and adopt a healthy eating lifestyle! Eat whole foods instead of processed foods. Drink water instead of sodas, juices and other beverages loaded with sugar or chemicals. And get out and walk, ride a bike or hike in a nearby park - just get yourself moving more!

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