Watermelon, carrots, squash and spinach. According to the European Journal of Nutrition, people who eat the most watermelon, carrots, squash and spinach have DNA that ages more slowly. As a result, those people have a lower risk of age-related problems, like Alzheimer’s, cancer and cardiovascular disease. The power is in the antioxidants that control the plant’s pigment! They’re called carotenoids, and they give fruits and vegetables their bright colors – and help protect against disease by fortifying cells from damage. So load up on watermelon, carrots, squash and spinach.