NYT reviews weight gain/loss research

[firecat]

The New York Times excerpts Gina Kolata’s new book, Rethinking Thin: The New Science of Weight Loss — and the Myths and Realities of Dieting reviews early human experiments on weight loss and gain. (free registration required)

http://www.nytimes.com/2007/05/08/health/08fat.html

A 1959 experiment on very low calorie dieting found that "fat people who lost large amounts of weight might look like someone who was never fat, but they were very different. In fact, by every metabolic measurement, they seemed like people who were starving....The Rockefeller subjects also had a psychiatric syndrome, called semi-starvation neurosis, which had been noticed before in people of normal weight who had been starved. They dreamed of food, they fantasized about food or about breaking their diet. They were anxious and depressed; some had thoughts of suicide. They secreted food in their rooms. And they binged."

and

Dr. Ethan Sims at the University of Vermont...asked what would happen if thin people who had never had a weight problem deliberately got fat.

His subjects were prisoners at a nearby state prison who volunteered to gain weight. With great difficulty, they succeeded, increasing their weight by 20 percent to 25 percent. But it took them four to six months, eating as much as they could every day. Some consumed 10,000 calories a day, an amount so incredible that it would be hard to believe, were it not for the fact that there were attendants present at each meal who dutifully recorded everything the men ate.

Once the men were fat, their metabolisms increased by 50 percent. They needed more than 2,700 calories per square meter of their body surface to stay fat but needed just 1,800 calories per square meter to maintain their normal weight.

When the study ended, the prisoners had no trouble losing weight. Within months, they were back to normal and effortlessly stayed there.

Comments

[bastette-joyce.livejournal.com]

One reason "Americans are getting fatter" (than we were) is that the Baby Boomers are aging. Lots of people gain weight as they age, and since this population is so large, it's affecting the national average noticeably.

And, I've said this a lot because many people seem to forget it (probably not people reading this, because most size activists have been paying attention to this), but 9 years ago, the national threshold for "obesity" was lowered, allowing millions of people who were merely "overweight" to become "obese" overnight. Unless that change is adjusted for, it just looks like there was a sudden jump in fat people over the past decade.

It would be interesting to get real data on weight statistics from other countries, particularly from countries that are similar to the US - ie, Westernized, industrial, and wealthy countries - that would have similar conditions to ours, so comparisons would make some sense.

The bell curve for height has also been nudged up over the past century. But everybody considers the environmental impact to be small compared to the genetic influence.

Actually, 100 years would have no impact whatsoever on the overall genetic change of a population (unless there was some sort of cataclysm, weeding out all but a few members of the population). So the fact that we're taller than we were 100 years ago actually is due to environment - specifically, changes in our diet. (More meat protein, I think.)

[mjlayman.livejournal.com]

I have a friend who has been actually skinny, not average, for the more than a decade that I've known him (people who've known him longer knew him as very fat and he reads Usenet while on a treadmill to maintain his lower weight) and he's actually "obese" by BMI standards. Makes you wonder.