WASHINGTON — Diet and exercise have long been the mantra for weight loss, but new research is showing food quality trumps counting calories when it comes to long-term weight loss.

Long-term weight loss is about what foods you eat and not just how much of them you eat, says Dr. David Ludwig, director of the Obesity Prevention Center at Boston Children’s Hospital. He worked on the research published in the Journal of the American Medical Association on June 4.

“Very few people can lose weight over the long term with low-calorie diets and those who can’t are blamed for lacking willpower,” Ludwig said on WTOP Monday morning.

Ludwig says the problem lies in refined carbohydrates. These types of carbohydrates include sweeteners, flours and white rice, among other foods.

Eating too many refined carbohydrates leads to increased insulin levels and programs fat cells to suck in and store calories. When that happens, there are too few calories for the rest of the body and the brain triggers a starvation response, which slows down metabolism and creates the feeling of hunger.

Cutting back on refined carbohydrates is the best way to achieve long-term weight loss.

“By doing this, you can pretty much ignore calories and let your own body weight control systems do the rest,” Ludwig says.

Eliminating fats from your diet isn’t the right way to lose weight either, Ludwig says.

Fat-free foods use other substitutes, which could be pumping your body with the wrong kinds of ingredients.

“When you get rid of fat, the food tastes terrible,” he says, explaining why fat-free foods contain substitutes.

Fats are among the healthiest foods you can eat — but they have to be the right kind of fats, he says. Fatty foods such as nuts, avocados, fish and olive oil can protect against heart disease and diabetes and can help with weight loss.

h/t: TIME

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