Magnesium
Background
The mineral magnesium functions as an essential cofactor for more than 300 enzymes. Magnesium deficiency has been associated with hypertension, insulin resistance, glucose intolerance, high cholesterol, increased blood clotting, cardiovascular disease, diabetic complications, and complications of pregnancy. Magnesium is one of the more common micronutrient deficiencies in diabetes. Decreased magnesium levels and increased urinary magnesium losses have been documented in both Type I and Type II diabetic patients. In addition, the use of certain medications, including diuretics, can deplete magnesium. Gastrointestinal malabsorption syndromes, low stomach acid (hypochlorydria), diets low in minerals, and alcohol abuse can also cause magnesium depletion.
Clinical Studies
Research has found that low levels of magnesium are associated with poor glycemic control, lower insulin sensitivity, cardiovascular disease, and increased microvascular complications of diabetes. Studies of magnesium supplementation have shown a mild positive effect on insulin sensitivity and triglyceride levels, but mixed results in terms of blood sugar control.
Recent studies have demonstrated that magnesium supplementation may offer protection from the development of NIDDM. One study observed marked magnesium deficiency in 11 well-controlled Type II diabetics; supplementation over 8 weeks significantly raised free intracellular magnesium in the subjects. The protective aspect of magnesium was isolated by another study that examined the effect of magnesium supplementation on obese rats over a period of 6 weeks. By the end of the study period, all of the control animals became diabetic, while only one of the eight rats in the supplementation group developed the disease. By preventing deterioration of glucose tolerance, magnesium may thus delay or prevent Type II diabetes.
Dosage
The America Diabetic Association recommends assessment of magnesium status in patients at risk for deficiency and supplementation for deficiencies. Research suggests that relatively high doses of magnesium for 3 months, followed by lower daily supplements, are needed to restore and maintain magnesium in people with diabetes. Doses of 300 to 600 mg per day of magnesium citrate are appropriate for patients with normal kidney function. Good dietary sources include whole grains, leafy green vegetables, legumes, nuts, and fish. Diets high in saturated fat, sugar, fructose, caffeine, and alcohol may increase magnesium requirements. Magnesium therapy should only be undertaken with the guidance of a healthcare practitioner familiar with its use.
