Magnesium is one of the seven essential macro minerals (requiring greater than or equal to 100mg/day).
The human body contains approximately 20-28 grams of magnesium. Over 50% of that magnesium is stored in the skeletal system, and the rest is found in muscle, soft tissues and bodily fluids.2
Magnesium plays an important role in over 300 enzymatic reactions within the body including the metabolism of food and synthesis of fatty acids and proteins. Magnesium is involved in neuromuscular transmission and activity and muscle relaxation. Magnesium deficiency, especially prevalent in older populations, is linked to insulin resistance, metabolic syndrome, coronary heart disease and osteoporosis.
This MNT Knowledge Center feature is part of a collection of articles on the health benefits of key vitamins and minerals. It provides an in-depth look at recommended intake of magnesium, its effects on health health, foods high in magnesium and any potential health risks of consuming magnesium.
Possible health benefits of magnesium
The following possible benefits have been associated with magnesium.
1) Bone health
Magnesium supplements are available from stores, but it is always best to obtain any vitamin or mineral through food.
Magnesium is important for bone formation as it helps with the assimilation of calcium into bone, and plays a role in activating vitamin D in the kidneys (vitamin D is also essential for healthy bones).
Optimal magnesium intake is associated with greater bone density and improved bone crystal formation, as well as a lower risk of osteoporosis in postmenopausal women.
Several studies have confirmed the inverse relationship between magnesium intake and the risk of diabetes. For every 100mg/day increase in magnesium intake (up to a point), the risk of developing type 2 diabetes decreases by approximately 15%. Most magnesium intake in these studies was from dietary sources, not supplements. Clinical studies have shown improvement in insulin sensitivity with magnesium intake between 300 and 365 mg/day.1
Researchers were also able to show that low magnesium levels resulted in impaired insulin secretion and lower insulin sensitivity. Since magnesium plays an important role in carbohydrate and glucose metabolism, it is no wonder magnesium status has an effect on diabetes.
3) Heart health
Magnesium is needed for the health of muscles, including the heart, and for the transmission of electrical signals in the body. Adequate magnesium intake has been associated with a lower risk of atherosclerosis and hypertension.
More recently, several studies have found that a high intake of calcium without sufficient magnesium could increase the risk of arterial calcification and cardiovascular disease, as well as kidney stones.6
People with the highest intake of magnesium were found in the Framingham Heart Study to have a 58% lower chance of having coronary artery calcification and a 34% lower chance of abdominal artery calcification.5
Rapid post-heart attack administration of magnesium reduces the risk of mortality, and magnesium is sometimes used as part of the treatment for congestive heart failure in order to lessen the risk of arrhythmia (abnormal heart rhythm).
Improvement in lipid profiles has been seen with an intake of 365 mg of magnesium per day.
4) Premenstrual syndrome
Research suggests that people experiencing premenstrual syndrome may be able to alleviate symptoms such as bloating, insomnia, leg swelling, weight gain, and breast tenderness by ensuring adequate intake of magnesium. Magnesium combined with vitamin B6 appears to be more efficacious.7
On the next page we examine recommended magnesium intake, foods that are high in magnesium and we discuss the possible health risks associated with consuming too much magnesium.