Paleo. Whole 30. Ketogenic. DASH. Atkins. Flexitarian. Weight Watchers. The list of diets, and their various restrictions, rules and regulations, goes on and on.
The estimated 45 million Americans who embark on one of these eating plans each year often do so to lose weight — a highly personal process that can lead to various results. One person finds success cutting carbs. Another swears by going vegan. A third fills up on healthy fats. Each one believes she’s found the elusive secret to weight loss.
An ever-growing body of evidence, however, suggests there’s no such thing as a single “best” diet — and that nutrition is a whole lot simpler than our fascination with fads would suggest.
Earlier this month, the Endocrine Society released a scientific statement saying that people can lose weight on any of roughly a dozen diets assessed by its researchers. A study published in February, meanwhile, found near-identical weight-loss benefits from low-carb versus low-fat diets. Another paper, published just a week later, said vegetarian and Mediterranean diets are equally heart-healthy.
In aggregate, these results suggest a less rigid approach to dieting. “There isn’t any one diet that anybody has to follow,” says Christopher Gardner, director of nutrition studies at the Stanford Prevention Research Center and the first author of last month’s low-carb versus low-fat study.
That’s a conclusion that Dr. David Katz, founding director of Yale University’s Yale-Griffin Prevention Research Center, says is far more novel than it should be. “The fact that whole foods, close to nature, mostly plants, are good for people: that never changes,” says Katz. “It’s the fundamental truth we’re not willing to accept.”
Part of the problem, Katz says, is public confusion. New eating plans and “superfoods” are constantly cast as the keys to health, and consumers can feel overwhelmed by choice and information. The food industry, and its constant stream of new products and nutrition gimmicks, is complicit in this confusion, Katz says. But so are the researchers who set out to find something novel simply to generate publicity, he says, and the news outlets that cover them.
It’s this environment, Katz says, that makes it seem like we don’t know much about nutrition. When a headline on Monday says carbs are bad, and a story on Wednesday says they’re good, people toss up their hands and say, “‘While they fight it out, you can find me at Burger King,’” Katz says.
But when you cut through the headlines, marketing campaigns and studies, he says, you’ll find that most experts agree on a few fundamentals of nutrition: that vegetables, fruits, whole grains, beans, lentils, nuts, seeds and plain water should make up the majority of what people eat and drink. If there is such a thing as a “best” diet, he says, that’s it.