From the department of what we already knew, but now have proof of: Middle-aged women who favor whole grains over white bread and other refined grains may put on fewer pounds as they age, a large study suggests. Harvard researchers found that among 74,000 women, those who ate more fiber-rich grains--such as oatmeal and whole-grain breakfast cereals--gained less weight over time than women who got the least fiber in their diets. In addition, women with the highest fiber intake were half as likely as those with the lowest intake to become obese over 12 years. In contrast, diets heavy in refined-grain products like white bread and pasta were linked to greater weight gain over time.