The title of a recent New Yorker essay by Jerome Groopman.
The problem with most diet books, and with popular-science books about diet, is that their impact relies on giving us simple answers, shorn of attendant complexities: it’s all about fat, or carbs, or how many meals you eat (the Warrior diet), or combinations of food groups, or intervalic fasting (the 5:2 diet), or nutritional genomics (sticking to the foods your distant ancestors may have eaten, assuming you even know where your folks were during the Paleolithic era). They hold out the hope that, if you just fix one thing, your whole life will be better.
In laboratories, it’s a different story, and it sometimes seems that the more sophisticated nutritional science becomes the less any single factor predominates, and the less sure we are of anything. Today’s findings regularly overturn yesterday’s promising hypotheses.
On top of that:
. . . research seems to undermine the whole idea of dieting: extreme regimens pose dangers, such as the risk of damaged kidneys from a buildup of excess uric acid during high-protein diets; and population studies have shown that being a tad overweight may actually be fine. Even studying these issues in the first place can be problematic. Although the study of the Mediterranean diet, for example, reflects randomized controlled experiments, most nutritional studies are observational; they rely on so-called food diaries, in which subjects record what they remember about their daily intake. Such diaries are notoriously inexact. No one likes admitting to having indulged in foods that they know—or think they know—are bad for them.
What to do?
Amid the constant back-and-forth of various hypotheses, orthodoxies, and fads, it’s more important to pay attention to the gradual advances, such as our understanding of calories and vitamins or the consensus among studies showing that trans fats exacerbate cardiovascular disease. What this means for most of us is that common sense should prevail. Eat and exercise in moderation; maintain a diet consisting of balanced amounts of protein, fat, and carbohydrates; make sure you get plenty of fruit and vegetables. And enjoy an occasional slice of chocolate cake.
The problem with that, common sense is not common.