Whatever the metabolic reason for this syndrome, says John Speth, an archaeologist at the University of Michigan’s Museum of Anthropology, plenty of evidence shows that hunters through the ages avoided protein excesses, discarding fat-depleted animals even when food was scarce. Early pioneers and trappers in North America encountered what looks like a similar affliction, sometimes referred to as rabbit starvation because rabbit meat is notoriously lean. Forced to subsist on fat-deficient meat, the men would gorge themselves, yet wither away. Protein can’t be the sole source of energy for humans, concludes Cordain. Anyone eating a meaty diet that is low in carbohydrates must have fat as well.

KELP

Stefansson had arrived at this conclusion, too, while living among the Copper Eskimo. He recalled how he and his Eskimo companions had become quite ill after weeks of eating “caribou so skinny that there was no appreciable fat behind the eyes or in the marrow.” Later he agreed to repeat the miserable experience at Bellevue Hospital, for science’s sake, and for a while ate nothing but defatted meat. “The symptoms brought on at Bellevue by an incomplete meat diet [lean without fat] were exactly the same as in the Arctic . . . diarrhea and a feeling of general baffling discomfort,” he wrote. He was restored with a fat fix but “had lost considerable weight.” For the remainder of his year on meat, Stefansson tucked into his rations of chops and steaks with fat intact. “A normal meat diet is not a high-protein diet,” he pronounced. “We were really getting three-quarters of our calories from fat.” (Fat is more than twice as calorie dense as protein or carbohydrate, but even so, that’s a lot of lard. A typical U.S diet provides about 35 percent of its calories from fat.)


Stefansson dropped 10 pounds on his meat-and-fat regimen and remarked on its “slenderizing” aspect, so perhaps it’s no surprise he’s been co-opted as a posthumous poster boy for Atkins-type diets. No discussion about diet these days can avoid Atkins. Even some researchers interviewed for this article couldn’t resist referring to the Inuit way of eating as the “original Atkins.” “Superficially, at a macronutrient level, the two diets certainly look similar,” allows Samuel Klein, a nutrition researcher at Washington University in St. Louis, who’s attempting to study how Atkins stacks up against conventional weight-loss diets. Like the Inuit diet, Atkins is low in carbohydrates and very high in fat. But numerous researchers, including Klein, point out that there are profound differences between the two diets, beginning with the type of meat and fat eaten.

Fats have been demonized in the United States, says Eric Dewailly, a professor of preventive medicine at Laval University in Quebec. But all fats are not created equal. This lies at the heart of a paradox—the Inuit paradox, if you will. In the Nunavik villages in northern Quebec, adults over 40 get almost half their calories from native foods, says Dewailly, and they don’t die of heart attacks at nearly the same rates as other Canadians or Americans. Their cardiac death rate is about half of ours, he says. As someone who looks for links between diet and cardiovascular health, he’s intrigued by that reduced risk. Because the traditional Inuit diet is “so restricted,” he says, it’s easier to study than the famously heart-healthy Mediterranean diet, with its cornucopia of vegetables, fruits, grains, herbs, spices, olive oil, and red wine.

A key difference in the typical Nunavik Inuit’s diet is that more than 50 percent of the calories in Inuit native foods come from fats. Much more important, the fats come from wild animals.

Wild-animal fats are different from both farm-animal fats and processed fats, says Dewailly. Farm animals, cooped up and stuffed with agricultural grains (carbohydrates) typically have lots of solid, highly saturated fat. Much of our processed food is also riddled with solid fats, or so-called trans fats, such as the reengineered vegetable oils and shortenings cached in baked goods and snacks. “A lot of the packaged food on supermarket shelves contains them. So do commercial french fries,” Dewailly adds.

Trans fats are polyunsaturated vegetable oils tricked up to make them more solid at room temperature. Manufacturers do this by hydrogenating the oils—adding extra hydrogen atoms to their molecular structures—which “twists” their shapes. Dewailly makes twisting sound less like a chemical transformation than a perversion, an act of public-health sabotage: “These man-made fats are dangerous, even worse for the heart than saturated fats.” They not only lower high-density lipoprotein cholesterol (HDL, the “good” cholesterol) but they also raise low-density lipoprotein cholesterol (LDL, the “bad” cholesterol) and triglycerides, he says. In the process, trans fats set the stage for heart attacks because they lead to the increase of fatty buildup in artery walls.

Wild animals that range freely and eat what nature intended, says Dewailly, have fat that is far more healthful. Less of their fat is saturated, and more of it is in the monounsaturated form (like olive oil). What’s more, cold-water fishes and sea mammals are particularly rich in polyunsaturated fats called n-3 fatty acids or omega-3 fatty acids. These fats appear to benefit the heart and vascular system. But the polyunsaturated fats in most Americans’ diets are the omega-6 fatty acids supplied by vegetable oils. By contrast, whale blubber consists of 70 percent monounsaturated fat and close to 30 percent omega-3s, says Dewailly.