The truth about diet cults

Author Matt Fitzgerald shares the five most interesting things he learned while writing his latest book.

From Atkins to Zone and everything in between, there has been a near-constant stream of diet philosophies infiltrating the zeitgeist and jockeying for authority. And as author Matt Fitzgerald points out in his new book,Diet Cults, each school of thought believes—strongly—that theirs is the only right way to stay lean. After poring over scads of research, Fitzgerald gained a unique perspective on our cultural fixation with dieting. Here, he breaks down the five most interesting truths he uncovered while sorting through the hype.

much like adults, babies are judging your diet.

Yale psychologist Karen Wynn studies infant morality by tracking babies’ attentional focus as they watch puppets engage in various behaviors before being either punished or rewarded. In one study, Wynn found clear indications that babies prefer puppets who share their own food preferences and expect them to behave better generally as well. Such behavior seems little different from the negative judgments that followers of various dietary philosophies levy against one another!

there are no common (eating) patterns among successful dieters.

In 1994, obesity researchers Rena Wing and James Hill formed the National Weight Control Registry, a kind of scientific club that’s open to anyone who has lost at least 30 pounds and kept the weight off at least one year. Nine years later, Hill confessed, “We could not find factors common to the diets" used by the successful losers. What Hill and Wing did find was evidence of a very high level of motivation for weight loss in registry members. So it appears that a person who is utterly determined to lose weight permanently is bound to succeed, regardless of which diet he or she chooses. On the flipside, a person who is less than determined is almost certain to fail, again regardless of his or her choice of diet.

92 percent of people who believe they're gluten intolerant are not.

The current hysteria surrounding gluten has inspired many folks with digestive issues to blame their symptoms on this maligned wheat protein. But when Peter Gibson of Australia’s Monash University gathered 37 people with self-diagnosed gluten intolerance for testing, he found that only three of them had a negative reaction to gluten consumption.

people can adapt to drastic changes in diet in just three days.

In a 2013 study, researchers at Duke University switched 10 subjects from their normal diet to either a vegan diet or a diet consisting primarily of meat and dairy. Within three days of making these changes, the subjects exhibited drastic shifts in the types of bacteria present in their digestive tracts—shifts that helped their bodies better process their one-sided diets. These findings challenge the contention of Paleo diet advocates that genetic evolution, which takes tens of thousands of years to unfold, is the only mechanism that allows animals (including humans) to adapt to big changes in diet.

humans can survive (and be quite healthy) on a virtually all-potato diet.

In the late 19th century, the Danish physician Mikkel Hindhede conducted an experiment in which he ate nothing but potatoes plus small amounts of milk and butter for many months. He concluded that “man can retain full vigor for a year or longer on a diet of potatoes and fat.” A decade later, these results were validated by Polish researchers Stanislaw Kon and Aniela Kline. And in 2011, Chris Voigt, head of the Washington State Potato Commission, ate nothing but potatoes for 60 days to protest a government proposal to remove potatoes from school lunches. Over that two-month period Voigt’s triglyceride, total cholesterol, and fasting glucose levels showed significant improvements.