Adding more fruits and vegetables to your diet is a good idea for many reasons, and weight control is one of them. But some vegetables are associated with weight gain, according to a Harvard study published Sept. 22, 2015, in PLOS Medicine. Researchers analyzed weight and diet changes in about 118,000 people over 24 years, at roughly four-year intervals. On average, people who increased their intake of fruits (especially berries, apples, and pears) and most vegetables, especially high-fiber, low-glycemic-load vegetables such as broccoli and Brussels sprouts, lost a little weight. In contrast, people who ate more starchy vegetables—peas and corn, for example—tended to pack on more pounds over time. This didn't prove that certain vegetables caused weight gain. "But we suspect the association may have something to do with the fact that starchy vegetables have a high glycemic load, meaning they spike blood sugar more than other foods," says Dr. Monica Bertoia, a Harvard Medical School instructor and lead author of the study.