The End of Craving: Recovering the Lost Wisdom of Eating Well
Mark Schatzker
Introduction: The Mystery
On a sunny September day in 2014, in the Jasmine Room at the DoubleTree hotel in Bethesda, Maryland, the mystery was food. There are many mysteries when it comes to food, but this was the big one, a nutritional debate that had been raging for decades: What makes people gain weight, carbs or fat? A scientist named Kevin Hall, from the National Institutes of Health, was standing at the lectern advancing slides in PowerPoint, preparing to deliver the answer.
IT IS a debate that stretches back at least as far as 1972, with the publication of Dr. Atkins' Diet Revolution: The High Calorie Way to Stay Thin Forever, one of the most influential diet books of all time. Humans, Dr. Atkins argued, had naturally evolved to eat meat but were being fed carbohydrates, to which they were “allergic,” and which made them accumulate fat. His advice was simple: stop eating bread and cereal and drinking fruit juice. Instead, eat more of what humans were meant to consume: cheese, eggs, and meat.
Dr. Atkins, alas, was twenty years too early to his own party. In 1977, the American government released Dietary Goals for the United States, a document that urged the nation to "increase carbohydrate consumption" and cut down on butterfat, eggs, and red meat. Atkins’s anti-carb message was quickly drowned out by a growing national crusade against fat. Americans became ever more sure that everything wrong with their diet was all the fault of this single nutritional villain. Why did people get fat? Because they ate fat. So Americans declared war on nature’s most calorically potent macronutrient. Diet salad dressings were poured on iceberg lettuce. Sandwiches were made with low-fat mayonnaise, lean slices of turkey breast, and low-fat cheese. At dinner, skinless breast of chicken was served next to a mound of steamed rice and boiled vegetables. At brunch, the true nutrition sophisticates asked that the omelet please be made from egg whites.
It was all a mammoth failure. Despite all those lean, hard-fought years of avoiding fat, the nation got fatter. All that supposedly healthy food didn’t reduce obesity—it pushed the national rate up by fifteen points. More than two decades after Dr. Atkins sounded the alarm against carbohydrates, America was finally ready to take his advice.
Almost overnight, meat was back. Guests would show up to dinner parties and refuse the salad, refuse the garlic bread, and refuse the potatoes, but help themselves to three portions of flank steak. Around the watercooler, coworkers shared stories of the crippling carb cravings and heinous farting that accompanied the miracle of high-fat weight loss.
In 2002, a science writer named Gary Taubes published a sensationally popular article in the New York Times Magazine called “What If It’s All Been a Big Fat Lie?” In it, he articulated what would become the leading dietary theme of a generation: “It’s not the fat that makes us fat, but the carbohydrates, and if we eat less carbohydrates we will lose weight and live longer.” Taubes would go on to publish several deeply researched books as more scientists and doctors joined the anti-carb camp. What had started as a too-good-to-be-true fad diet featuring unlimited bacon was beginning to seem as if it might work. The country’s love of bread, pasta, rice, chips, doughnuts, fruit juice, and soft drinks came to seem like nutritional suicide. Taubes even introduced America to the hormone at the root of the problem.
In 2009, Gary Taubes visited the National Institutes of Health to give a talk on the carbohydrate-insulin model. Kevin Hall was in the audience. Hall was an agnostic when it came to the carbs-versus-fat debate. His PhD was in physics, and he was developing a complex mathematical model of human metabolism. But Taubes’s argument had a compelling logic. If the human body is capable of using both fat and carbohydrates as fuel, it seemed reasonable that one might have a metabolic advantage over the other. A couple of years later, Hall proposed doing a rigorous study in which subjects were kept in a hospital setting and fed each diet while researchers measured precisely how the energy was being burned. Taubes was game. He had recently formed a nonprofit called the Nutrition Science Initiative (NuSI), which had received millions of dollars in funding.
学术型科普书。大量篇幅都是在介绍历史上的科研过程，读来妙趣横生。