Calcium helps prevent osteoporosis and helps maintain bone density health. Milk, cheese, and dairy are foods highest in calcium. And, as you get older, you need to increase your intake. Don’t eat dairy? How about some sardines and kale? If you’re like most of us, probably not going to happen. In this case, you’ll need a supplement. If you’re a woman over 70 or prone to kidney stones, cap your intake at 500 mg.