Nutrition Notes: The Magnesium Link

We know our dietary choices affect our health risks, but recent studies highlight a reason we probably wouldn’t think of: adequate amounts of magnesium could reduce the risk of diabetes by 10% to 34%.

In a study of over 39,000 women, those who were getting the most magnesium had an 11% lower risk of developing diabetes six years later than those who got the least. Among overweight women the magnesium impact was even stronger: risk fell more than 20%.

In two other studies of more than 85,000 women and 42,000 men, individuals who consumed the most magnesium lowered their risk of developing diabetes more than 30% during the next 12 to 18 years compared to those who consumed the least amount.

The conclusions of these three studies are generally supported by earlier large population studies. Laboratory studies suggest that magnesium influences the action of insulin in the body. A lack of magnesium may worsen insulin resistance, triggering the onset of diabetes — a disease now said to be afflicting North Americans at almost “epidemic” levels.

Magnesium may also affect other health conditions. Adequate magnesium may lower the risk of osteoporosis and play a role in blood pressure control. Although magnesium lacks a direct link so far to cancer prevention, foods that are good sources of magnesium supply nutrients and phytochemicals that help protect against cancer. If you create an eating pattern that provides magnesium, you will help lower your risk for essentially all of today’s top health risks, heart disease and stroke included.

High levels of magnesium are not necessary for risk reduction. In all three of the latest studies, the big difference in diabetes risk lies between people who met the Recommended Dietary Allowance (RDA) and those who stayed below it. The current RDA for magnesium is 310-320 mg for adult women, and 400-420 mg for adult men. Average intake among North Americans tends to lag about 100 mg below these recommended levels. Those most likely to have low blood levels include the elderly and those who take diuretic medications, which increase magnesium excretion.

The best food sources of magnesium are green leafy vegetables, whole grains, nuts and dried beans. Meat, milk and other starches are moderate suppliers. Because refined foods have the least, magnesium intake has dropped since we now eat more refined and processed foods than ever.

“Nutrition Notes” is provided as a public service by the American Institute for Cancer Research, 1759 R Street, NW, Washington, DC 20009