Your morning bowl of oatmeal may keep you from gasping for air during your afternoon run today—and for decades down the road. Why? It's packed with fiber, and a new study in the American Journal of Epidemiology found that people who consumed at least 27 grams of the nutrient a day had a larger lung capacity than those who took in less than 10 grams. What's more, those in the high-fiber group were 15 percent less likely to develop chronic obstructive pulmonary disease, a breathing disorder. "The fiber found in cereal and produce may reduce tissue inflammation that can damage lungs," says study author Stephanie London, M.D., Ph.D.