Of all the changes taking place on the food front, one of the most important concerns the balance between diet and exercise. It’s still true that to maintain a healthy weight, calories consumed must equal calories burned. Tip that balance one way and you drop pounds; tip it the other way and you gain. Period. Paragraph.
But this summer a landmark study in the New England Journal of Medicine found that it’s not just how much food you eat, but which kind, that influences weight gain. After adjusting for age, baseline body mass index and lifestyle factors such as exercise and sleep duration in 120,000 participants, the authors found that the foods most associated with adding pounds over a four-year period were french fries, potato chips, sugary drinks, meats, sweets and refined grains. The foods most associated with shedding pounds were yogurt, nuts, whole grains, fruits and vegetables.
But there’s more than simple caloric arithmetic at work here. When you sit down to a meal, your brain is looking for nutrients, not calories, and will prod you to eat until you’re satisfied. That’s one of the many reasons it’s harder to push away from a plate of fries or a bowl of ice cream than from a healthier meal of fruits, vegetables, grains and lean meats.
A similar matter of digestive mechanics is at work too. High-fiber foods expand in the stomach, slowing digestion and augmenting satiety. That’s the reason I try to eat fruit or a handful of nuts prior to a big meal. Consuming a controlled amount of calories from the right kind of food now helps avoid taking in many more calories from the wrong kind later.