Managing Diabetes with Magnesium?

Diabetes risk lowered among those with high magnesium intake new study shows

/ Author:  / Reviewed by: Joseph V. Madia, MD Beth Bolt, RPh

(RxWiki News) A healthy diet and exercise have been associated with lowering the risk for diabetes. Researchers behind a new study took a closer look at a very specific part of a healthy diet - magnesium intake.

According to the study authors, magnesium, found naturally in a variety of foods like spinach, legumes, nuts and whole grains, has been associated with controlling factors that can lead to diabetes.

In the new study, researchers found that higher magnesium intake was associated with a lower risk of developing diabetes.

"Eat a balanced diet with a variety of nutrients."

In type 2 diabetes, the body does not properly use the hormone insulin, leading to high blood glucose (sugar) levels. According to the American Diabetes Association (ADA), before type 2 diabetes develops, many patients have "prediabetes" - in which their blood glucose levels are higher than normal but not high enough to be considered diabetes.

Types of prediabetes conditions include impaired glucose tolerance (IGT) and impaired fasting glucose (IFG). The authors explored these conditions, as well as other forms of metabolic impairment, including insulin resistance (IR), in which the body's cells do not properly respond to insulin, and hyperinsulinemia, in which there are higher than normal levels of insulin in the blood.

The authors of the study, led by Adela Hruby, PhD, MPH, of the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University in Boston, wanted to explore potential connections between magnesium intake and metabolic impairment in otherwise healthy individuals. In people who already had metabolic impairment, the researchers looked for progression of these problems into type 2 diabetes.

Dr. Hruby and colleagues utilized data from The National Heart, Lung, and Blood Institute’s Framingham Heart Study to follow 2,582 adults between the ages of 26 and 81 years old for seven years. The average age was 54 years old, and none of the patients had diabetes at the study's outset.

Magnesium intake (through a food-frequency questionnaire) and metabolic impairment (through a glucose tolerance test) were measured. The data was analyzed by the researchers and adjusted for factors like age and gender.

The average magnesium intake was 308 milligrams (mg) per day. According to the authors of the study, the Recommended Dietary Allowance (RDA) for magnesium is 400 to 420 mg a day for adult men and 300 to 310 mg a day for adult women. Fifty percent of the female participants and 75 percent of the male participants reported magnesium intake levels below the RDA.

Among the 1,654 participants without metabolic impairment at the study's beginning, 307 cases of metabolic impairment, including 25 cases of diabetes, developed over the study's course. The researchers found that those with the highest magnesium intake had a 37 percent lower risk of metabolic impairment than those with the lowest amount of magnesium intake.

Among the 928 participants with metabolic issues at the start of the study, 154 cases of diabetes developed. The researchers found that those with the highest magnesium intake had a 32 percent lower risk of diabetes than those with the lowest amount of magnesium intake.

In combining these two groups, a total of 179 diabetes cases were seen. For the total study population, a higher magnesium intake was associated with a 51 percent lower risk of diabetes, the study authors reported.

"In conclusion, higher magnesium intake may lower risk of progressing to diabetes among those with the highest risk of doing so—namely, those with insulin resistance or prediabetes," Dr. Hruby and colleagues wrote. "These findings support a role for higher magnesium intake in those at high risk of developing diabetes, and the need for large, randomized trials to confirm these observations."

"Low magnesium on a blood test is one of the signs of diabetes, although many doctors do not routinely test for magnesium. Therefore it's great to see this study showing that people who eat a high-magnesium diet have a lower risk of diabetes. But I would caution that due to modern farming practices and food processing, there is only about 250mg of magnesium in a good diet, whereas 100 years ago there was 500mg, so I recommend people at risk for diabetes take supplemental forms of magnesium," Carolyn Dean, MD, ND, Medical Advisory Board Member of the non-profit Nutritional Magnesium Association, told dailyRx News.

"Magnesium citrate powder made into a tea with either hot or cold water is an easy way to get more magnesium in your diet. In my practice, I see people who begin to take magnesium lower their blood sugars and HgA1C levels, so magnesium not only prevents diabetes but it can be part of your treatment plan as well," said Dr. Dean.

The study authors noted that high magnesium intake could be associated with other health lifestyle factors which might impact diabetes risk. More research needs to be done to confirm the connection.

The study was published online October 2 by Diabetes Care, the journal of ADA. No conflicts of interest were reported.

Review Date: 
October 3, 2013
Last Updated:
October 9, 2013