Magnesium may help lower blood pressure, and may help prevent diabetes

Magnesium is sometimes called "nature's calcium channel blocker" because like that class of heart drugs, the mineral blocks calcium from entering cells, relaxing blood vessels and lowering blood pressure. The mineral is abundant in dark leafy greens, such as spinach, and in nuts, whole grains and beans. Most doctors--and the government--recommend 400 milligrams a day. Many people in the U.S. get less than 200 milligrams a day.