— Susan, Georgia Magnesium has hundreds of important functions in the body, from energy production and proper nerve function to muscle relaxation. Studies are mixed about whether its potential heart benefits come from the magnesium itself or from a combination of magnesium and other beneficial nutrients (such as potassium and fiber). Or perhaps it’s simply that people who eat a magnesium-rich diet are more health conscious in general. But there is no question that this important mineral plays a key role in the prevention of cardiovascular disease. Here’s a crash course in what magnesium can do to help your heart: Regulate heart rhythm. Just as it helps nerve function throughout the body, magnesium is important for coordinating the activity of the heart muscle and the nerves that initiate the heartbeat. If your magnesium levels are low, you are more likely to be at risk for arrhythmias (irregular heartbeats) and heart palpitations. While doctors can temporarily stabilize irregular heartbeats with injections of a magnesium compound, this is generally not done except in an emergency situation. Prevent angina. Magnesium helps keep coronary arteries from having spasms, which is what causes the intense chest pain known as angina. In fact, a deficiency of magnesium is the most common cause of such arterial spasms. Control high blood pressure. By relaxing the muscles that control blood vessels and allowing blood to flow more freely, magnesium may play a role in reducing elevated blood pressure, an important factor in decreasing the risk for heart attack and stroke. Magnesium’s effect on high blood pressure is further enhanced because it helps equalize the levels of potassium and sodium in the blood. Limit complications of congestive heart failure. Because magnesium can help lower blood pressure and reduce the risk of arrhythmia, two frequent complications in those with congestive heart failure, a weakened heart may benefit from getting more of this mineral. Reduce incidence of prediabetes and diabetes and improve insulin resistance. Several important studies have demonstrated that getting insufficient amounts of magnesium increases the risk of metabolic syndrome (prediabetes), type 1 and type 2 diabetes, and the development of diabetes complications. Moreover, a magnesium deficiency can negatively affect fasting blood glucose and insulin levels in nondiabetic individuals (which often leads to diabetes). I believe, however, that more research is needed on the role of magnesium in diabetes prevention. Learn more in the Everyday Health Heart Health Center.