You may have read about the Minnesota Starvation Experiment, which began in late 1944 and ran through most of 1945; healthy, strong conscientious objectors and other volunteers decreased their body weight by 25%, under the direction of Dr Ancel Keys. In 2003 and 2004 a couple researchers interviewed the surviving participants as an oral history project, reported in “They Starved So That Others Be Better Fed: Remembering Ancel Keys and the Minnesota Experiment”, published in The Journal of Nutrition.
One of the things that struck me about this experiment was that most of the men exhibited social withdrawal, depression, preoccupation with food, increased susceptibility to infection, and lack of interest in sex – all of which I have found to accompany dieting in the long-term. (I am wondering if it’s a coincidence that my first bout with depression occurred after plateauing on the “I Love NY Diet” in high school.) The idea of a diet, of course, is that a diet only results in losing what your body “doesn’t need”. I’m not so sure, and I’m not alone. The research doesn’t agree, either.
(I do think a lot depends on where your body is at when you start the diet. If you’ve been above your setpoint, then eating less or exercising more may bring you down to your setpoint without adverse affects. Of course, you may also just find yourself doing this naturally, too. A bit like gaining back the 5lbs or 10lbs you lost with the flu – you don’t think about it, it just happens. But deliberately eating less than your body wants for months? Is Not A Good Idea.)
Lest you think the Minnesota experiment involved a 600-calorie diet, the participants were first observed and monitored on their normal diet of roughly 3200 calories / day. The semi-starvation began with each man being given 1800 calories a day and each man’s rations were adjusted during the starvation period to keep individual’s weight moving down as expected.
Finally, I would note that this research is still used in recovery from anorexia, bulimia, and other eating disorders. For example, the finding that the “restricted recovery phase” of a little more food (2000 calories) it was not enough for them to fully recuperate; for that, the unrestricted-eating phase was required.
And yet, I don’t see warnings that dieting can cause depression or anxiety in fine print of diet/WLS ads, despite research showing that dieting can also affect mental health, same as semi-stavation. From Jules Hirsch’s weight-loss studies at Rockefeller University:
Before the diet began, the fat subjects’ metabolism was normal — the number of calories burned per square meter of body surface was no different from that of people who had never been fat. But when they lost weight, they were burning as much as 24 percent fewer calories per square meter of their surface area than the calories consumed by those who were naturally thin.
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.
The Rockefeller researchers explained their observations in one of their papers: “It is entirely possible that weight reduction, instead of resulting in a normal state for obese patients, results in an abnormal state resembling that of starved nonobese individuals.”
When a healthy, normal-weight person loses 25% of his body mass and looks emaciated, we see it as semi-starvation. When a healthy fat person loses 25% of her body mass and still looks fat, we see it as, “Oh, well, you still have more to lose” — even though the affects on mental health and metabolism may still be the same.
- PBS has excerpts from participant Lester Glick’s diary of the experiment here.
- “They Starved So That Others Be Better Fed: Remembering Ancel Keys and the Minnesota Experiment”, Leah M. Kalm and Richard D. Semba, published in The Journal of Nutrition, June, 2005.
- Genes Take Charge, and Diets Fall By The Wayside, by Gina Kolata, published in The New York Times, May 8, 2007.