Interior design
Interior Design

Tuesday, August 25, 2009

The Minnesota Starvation Study

Just a few years before the Framingham study began, a very different type of experiment was already underway in Minnesota, led by Ancel Keys. Dr. Keys is known for his pioneering work on the link between saturated fat and heart disease and for the development of K-rations, the balanced, portable meals given to soldiers during World War II. But his study involving a group of thirty-six conscientious objectors who volunteered to starve for the sake of science ranks as his most intriguing yet controversial work. Today, ethical regulations would never allow this type of study to take place.

The purpose of the study was to understand the physical and mental effects of starvation, anticipating the need to learn the best ways to re-feed people who had experienced extreme starvation (namely, civilians throughout Europe after World War II). The men endured six months of semistarvation, eating a diet similar to that in war-torn Europe—lots of potatoes and turnips and very little meat or dairy products. During the study, the men had to continue exercising, walking at least 22 miles a week, or about 3 miles a day. They were rationed about 1,600 calories per day—approximately three quarters of what these healthy young men needed to stay at their previously normal weight levels.

The men lost an average of about 25% of their body weight over six months, which caused them to resemble the concentration camp survivors they were hoping to help. They became sluggish, uncoordinated, depressed, and irritable. Keys documented the study in a two-volume tome, The Biology of Human Starvation, which includes this description penned by one volunteer:

I’m hungry. I’m always hungry—not the hunger that comes when you miss lunch but a continual cry from the body for food. At times I can almost forget about it but there is nothing that can hold my interest for long.

These feelings may be familiar to veteran dieters who’ve tried very low-calorie diets. Even among people who are overweight or obese (unlike these normal-weight volunteers), the very same mechanisms kick in during the self-imposed starvation of a diet. Faced with the physical and emotional strain, the body fights back to stay alive. Keys calculated that the men’s metabolic rates had decreased by about 40% by the end of the starvation period. One volunteer said it was as if his "body flame [was] burning as low as possible to conserve precious fuel and still maintain [the] life process."

After six months of starvation, the men entered a rehabilitation phase, during which they gradually received increasing amounts of food over a three-month period. Perhaps not surprisingly, the men’s response to this relative abundance provoked some unusual behaviors. Some ate until they vomited and then asked for more. Others ate until they weren’t physically capable of eating another bite of food, yet they still claimed they were hungry. Again, these behaviors may sound familiar to people who’ve tried so-called crash diets designed for rapid weight loss.

The take-home lesson is that it’s extremely challenging to try to lose a lot of weight over a short time period. Your body will rebel against these efforts, helping you regain the weight you’ve lost and possibly triggering strange (and potentially unhealthy) eating behaviors.



Source: George L. Blackburn, M.D., Ph.D., "Break Through Your Set Point: How to Finally Lose the Weight You Want and Keep It Off," 2008

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