In 1826, the French epicure Jean Anthelme Brillat-Savarin wrote, “Tell me what you eat and I’ll tell you what you are.” A couple decades later, a German philosopher penned, “Man is what he eats.” And in the U.S. in the 1940s, nutritionist Victor Lindlahr published “You Are What You Eat: How to Win and Keep Health with Diet.”

Now, researchers from Harvard have published a think piece, “The Carbohydrate-Insulin Model: A Physiological Perspective on the Obesity Pandemic,” in The American Journal of Clinical Nutrition. It suggests that overeating isn’t the main cause of obesity. Instead, it’s caused by what you eat.

They say eating foods with a high glycemic load, such as processed, rapidly-digested carbohydrates, triggers hormonal responses that profoundly change your metabolism, and lead to excessive fat storage. That excess fat storage leaves fewer calories circulating. And that deprives you of fuel and saps your energy, amping up hunger and leading to weight gain. The bottom line: It’s not just about overeating. What you eat has a huge impact on whether you have obesity or not.

If you’ve been struggling with weight control, you might ditch calorie counting and start counting your servings of vegetables and fruits (aim for seven daily). At the same time, banish highly processed foods (snacks, baked goods, sweets, white bread and any pasta that’s not 100% whole grain).

If you are what you eat, wouldn’t you rather be a beautiful ripe tomato, a sassy stalk of asparagus or a mysterious, layered artichoke than a flat, beige, mushy pancake?

Oz is host of “The Dr. Oz Show” and Roizen is chief wellness officer emeritus at Cleveland Clinic. To live your healthiest, tune into “The Dr. Oz Show” or visit www.sharecare.com.