You’ve heard it before: To lose weight, simply eat less and exercise more. In theory, that makes sense.

Actually, it’s not just in theory - science has shown that burning more calories than you consume will result in weight loss. But unfortunately that only yields short-term results.

Ultimately their argument is this: stop counting calories.

“We intuitively know that eat less exercise more doesn’t work. It’s such simple advice that if it worked, my colleagues and I would be out of job,” says Dr. David Ludwig, director of the New Balance Foundation Obesity Prevention Centre at Boston Children’s Hospital.

“The uncomfortable fact is that an exceedingly small number of people can lose a substantial amount of weight and keep it off following that advice.”

What, then, is causing the obesity epidemic? The authors say it’s refined carbohydrates. Sugar and processed grains like white bread which have become ubiquitous in our diets, and one of the reasons refined carbs is the prime culprit is that we’ve spent far too long chastising fat.

“We have to forget the low-fat paradigm,” says Dr. Ludwig. “Some high fat foods like avocado, nuts and olive oil are among the healthiest foods we could possibly eat.”

Instead of counting calories, we should be focusing on the quality of the food we ingest, says Ludwig. “If you just try to eat less and exercise more, most people will lose that battle. Metabolism wins,” Ludwig claims.

“Simply looking at calories is misguided at best and potentially harmful because it disregards how those calories are affecting our hormones and metabolism—and ultimately our ability to stick to a diet.”