Ancel Keys studies people eating a long term 1600 calorie diet and explains what "semi-starvation neurosis" means as the subjects broke down mentally and their weight loss slowed.
November 1, 1944
The Biology of Human Starvation
Ultimately, the question that can be easily answered and that certainly should be asked of anyone who suggests we can regain a healthy weight by eating less (let alone that this way is ordained by the laws of physics) is, At what cost? What are the side effects? What are the negative sequelae, as doctors with a fondness for Latin terminology would call them? We care about the side effects of any drug therapy for a disease. Does it give us headaches, make us drowsy or dizzy? Do we get abdominal pains or cramps, nausea, and vomiting? Diarrhea? Erectile dysfunction? If we take a drug to lower our cholesterol and it makes our muscles ache unbearably, we’re going to find another way or at least another drug to do that job. So what about dietary therapy, and eating less specifically? Imagine that we voluntarily decide to accept, as Keys suggested and Newburgh implied, that eating less is indeed an absolute requirement for weight loss and then continued weight maintenance. We aim to cut back sufficiently so that we become relatively lean and stay that way for a lifetime. What might that entail? What are the common side effects? What will we have to endure?
The authorities know the answer to this question, which may be why they rarely if ever ask it. The relevant seminal study, the one that has stood for decades as incontrovertible evidence (such as there is in nutrition research), was conducted in the early 1940s by Ancel Keys. He and his colleagues then wrote a two-volume tome, nearly 1,400 pages total, about all that they had learned. The title, The Biology of Human Starvation, immediately tells us a little about what he did and what the experience must have been like for the experimental subjects, who provided the answer to the question of what happens if we try to live with the kind of caloric deprivation that the authorities often argue is necessary for significant weight loss.
Put simply, we get hungry, exceedingly so. “The best definition of food deficiency,” as Keys and his colleagues wrote in The Biology of Human Starvation, “is to be found in the consequences of it.” In the early years of World War II, Keys and his University of Minnesota collaborators enlisted three dozen conscientious objectors for the experiment. Most of these young men were lean; a few were heavy, at least by the standards of that considerably leaner era. Keys and his collaborators fed them roughly 1,600 calories daily of what would today be considered a very healthy if very boring diet: “whole-wheat bread, potatoes, cereals and considerable amounts of turnips and cabbage” with “token amounts” of meat and dairy. It was a low-fat diet, as nutritionists would call it, low in saturated fat surely, so it was right in line with the dietary guidelines of most twenty-first-century health organizations. The calorie level would put it well within the range recommended for weight loss today.
For the first twelve weeks, the men lost an average of a pound of body fat a week, but this slowed to a quarter pound weekly for the next twelve, despite the continued deprivation. In total, that’s an average of fifteen pounds of fat shed over almost half a year. Not bad, although certainly not all that great (keeping in mind that these men did not have that much excess weight to lose). This, however, was not their only response. The men felt continually cold. Their metabolism slowed. Their hair fell out. They lost their libidos. They threw tantrums and thought obsessively about food, day and night. “Semi-starvation neurosis,” the Minnesota researchers called it. Four developed “character neurosis,” which was more severe. Two of those had breakdowns, one with “weeping, talk of suicide and threats of violence.” He was committed to a psychiatric ward. The “personality deterioration” of the other “culminated in two attempts at self-mutilation.” The first time he nearly cut off the tip of one finger with an ax. When that didn’t get him released from the study, he “accidentally” chopped off three fingers.
That’s quite a price to pay for eating a healthy, mostly plant, whole-food, low-fat diet of 1,600 calories a day. When these men were allowed at the end of the study to eat to satiety, they consumed prodigious amounts of food—up to 10,000 calories a day. They regained weight and fat remarkably fast. After twenty weeks of recovery, they averaged 50 percent fatter than when they started—they had “post-starvation obesity,” as Keys and his colleagues called it. Many of us have been there. We can relate. So we know that lean, healthy people can’t live with this kind of calorie restriction, not if they have any choice. Why expect a fat person to do it? In fact, you can ask any lean friends you might have, in all seriousness, what they would do if their goal in life or just for a single day was actually to make themselves hungry, to “build up an appetite” and keep it up. Tell them to imagine that they are invited to a feast that night, one with the best food they’ll ever eat, course after course after course. Tell them their goal is to come hungry and bring an appetite. Ask them what they’d do to make sure that happens. I’m willing to bet that they’ll suggest that they start by eating less during the day, skipping snacks, and reducing their portion sizes when they do eat, and they’ll probably also decide that exercising will help, or exercising more—going for longer walks or hikes, burning more calories on the elliptical machine at the gym. In short, eating less, exercising more.
Gary Taubes. The Case for Keto: Rethinking Weight Control and the Science and Practice of Low-Carb/High-Fat Eating (Kindle Locations 904-909). Knopf. Kindle Edition.