Published on Psychology Today (http://www.psychologytoday.com)
Dieting Can Make You Lose Your Mind
By Emily Deans, M.D.
Created Mar 24 2011 - 12:58pm
Why is it so hard, though, to keep off the pounds? Is it the huge restaurant portions? Is it all the food everywhere? Brownie advertisements? Video games? Somehow, even with our big brains and computers to do the simple work of tracking exercise and calories, we can't seem to get it together enough to prevent the obesity and the diabetes. But look out the window - you never see that family of squirrels with brains the size of your thumbnail (and an all-you-can-eat buffet of acorns) waddling through the yard, stricken with morbid obesity.
Scientists have been studying obesity and weight loss for generations. One of the most famous calorie-restriction studies was done on conscientious objectors during World War II by Dr. Ancel Keys. 36 healthy young men who had been excused from armed service for ethical objections agreed to a year long diet of sorts. It would include 3 months of preparation, 6 months of semi-starvation (designed to make the men lose 25% of their body weight), and then 3 months of refeeding. The purpose of the study was to determine how people would react under such conditions, and also to learn how to safely and successfully refeed starving populations. The men were highly motivated for the study, as their purpose was to help their country and the men fighting overseas who might face starving conditions themselves.
The young men lived in a dorm at the University of Minnesota, and in addition to their restricted diet, they were required to walk 22 miles a week. All their food was prepared in a dormitory kitchen, and once the starvation began, each man's calories were adjusted every Friday to meet a weight loss goal of 2.5 lbs (1.1 kg) per week. Their average daily calories during the semistarvation period was about 1600 calories a day (they ate approximately 3200 calories daily before the study). I find the number 1600 calories especially compelling, for a standard weight loss diet recommended for a woman is usually about 1200 calories daily. Their food consisted of what might have been available in war-torn Europe at the time - potatoes, turnips, rutabagas, dark bread, macaroni, small glasses of milk, chicken, toast with a small smear of jam, those kinds of things.
What was it like for them? Well, horrible. They described lethargy, irritability, anxiety that approached each time they were to learn how much they were allowed to eat the following week. They had to institute a buddy system so that none of the men were allowed to leave the dormitory alone, as one man went off diet and had to be excused from the study. They had dizziness, cold intolerance (requesting heavy blankets even in the middle of summer), muscle soreness, hair loss, reduced coordination, edema, and ringing in the ears. Some had to withdraw from their university classes because they did not have the capability to concentrate. Their sex drive disappeared. They became obsessed with food, eating with elaborate rituals (which eating disorder patients also do) and adding water to their plates to make the food last longer. Many collected cookbooks and recipes. One man, tempted by the odor from a bakery, bought a dozen doughnuts and gave them to children in the street just to watch them eat. Originally, the participants were allowed to chew gum, but when many of the men went to chewing about 40 sticks a day, it was decided that gum would affect the experiment and it was disallowed.
Only 32 of the original 36 completed the semistarvation period. One man who broke diet admitted to stealing scrapings from the garbage cans, stealing and eating raw rutabagas, and stopping at shops to eat sundaes. Two of the men suffered severe psychological stress - one became suicidal, and another cut off three of his fingers in an act of self-mutilation. Both men were taken to a psychiatric hospital.
The 3 month refeeding period involved trying several different combinations of protein, vitamins, and levels of calories. Dizziness, apathy and lethargy improved first, but persistent hunger, weakness, and loss of sex drive persisted for several months. The men described "a year long cavity" that needed to be filled. The day after they were finally released from the study, one of the men was hospitalized to have his stomach pumped after binging. In the aftermath of the study, "many, like Roscoe Hinkle, put on substantial weight: Boy did I add weight. Well, that was flab. You don't have muscle yet. And get[ting] the muscle back again, boy that's no fun." None who were interviewed in their 80s felt there was any lasting medical harm, once they'd recovered.
What strikes me the most about this study is how close it is to the standard recommendations for weight loss today (500-1000 calorie deficit daily for goal of 1-2 pounds lost a week, plus moderate exercise). The difference is by degree (1700 calorie deficit daily for goal of 2.5 pounds lost a week), and the fact that the men were normal weight when they began the study. But this strict diet sent 6% of the participants to the psychiatric hospital - and these were highly motivated, healthy young men! There is also a marked contrast between the psychological states in this long-term semi-starvation and reports of shorter-term water fasts. All told, prolonged semi-starvation on turnips and dark bread is not something I would recommend for anyone, if you can avoid it. Perhaps Mrs. Ancel Keys said it best, when she described the effects of the experiment on her husband: "Mrs. Keys said that Dr. Keys went through terrible times during the experiment as we lost weight and became gaunt and so on. And he would come home and say, ‘What am I doing to these young men? I had no idea it was going to be this hard.'"
What if, instead, we take a cue from the squirrels, and throw out the packaged meals and shakes, and eat the food our ancestors ate for thousands of generations. Those ancestors who likely never struggled with obesity or diabetes. We can even look at studies of the modern-day Kitavans, who eat starchy root vegetables, coconuts, and fish and seaweed, seem to have plenty of food, don't exercise all that much, but remain effortlessly slender and free of diabetes and the other diseases of civilization. Maybe a calorie isn't just a calorie. Maybe novel food products cause inflammation and irritation, leading to changes with insulin, leptin, and other appetite hormones. Perhaps that explanation would make more sense than the current one that, somehow, in a few generations, the majority of Americans have become hopeless gluttonous sloths.
Instead we keep running on the same treadmill, the same calorie counts and fat-free food. Along with obesity and diabetes, binge eating disorders and bulimia have increased over the years, and the population suffering from all these conditions keeps getting younger, and younger, and younger.
Don't lose hope. Hop off the treadmill and go for a long walk outside. Consider eating the food our ancestors ate (ditch the processed food, the sugar, and the grains for a while) and see what happens. You might find yourself eating the calories you need to sustain your particular physical activity level, and even burning some of your own fat to a new, lower bodyweight set point. Only domesticated, grain-eating animals have problems with obesity, after all. Let a little bit of of the wild back into your routine and habits. Your health might improve for it.
More articles like this one at Evolutionary Psychiatry.
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Copyright Emily Deans, M.D.
Source URL: http://www.psychologytoday.com/node/57568
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