We talk a lot about how weight and lack of exercise play an important role in heart disease. But there is actually evidence linking excessive weight and sedentary lifestyle to many other health problems. For example, the American Institute for Cancer Research estimates that more than 1/3rd of common cancers could be prevented by eating a healthy diet, exercising regularly and maintaining a healthy weight. The new USDA Dietary Guidelines just released support these same goals in their recommendations. You can find a summary of the new guidelines here.