There is no cure for osteoporosis. A person can keep it from happening by exercising and taking the right amount of calcium each day. 75 million people in the United States, Japan, and Europe have osteoporosis. 30 million people in the US have poor bone density. Vitamin D, calcium, and exercise are the three main things for healthy bones. Consuming too much alcohol and caffeine can cause an increase in the risk of weak bones. Too much salt increases the amount of calcium lost in urine. This is bad because calcium makes bones strong. People should not take iron and calcium supplements at the same time. This is because calcium competes with the absorption of minerals such as iron.