Summary
Adequate intake of magnesium has been found to reduce insulin resistance. In this research study, the effect of oral magnesium on insulin sensitivity and metabolic syndrome in overweight, non-diabetic people with normal magnesium levels and insulin resistance was tested. An oral glucose tolerance test was used as a measure to check eligibility for participation in the trial. A randomized trial was done for proper observation. This research emphasizes optimum intake of magnesium to prevent insulin resistance and consequently type 2 diabetes.

Introduction
Several research studies have shown that magnesium has an important role in ameliorating insulin resistance and metabolic syndrome. The benefit of this feature is that it can prevent onset of type 2 diabetes. Very little is known about the preventive or therapeutic effects of magnesium on early changes in the glucose levels in human body. Some other investigations have shown a positive effect of magnesium supplementation in reducing fasting glucose levels in patients with type 2 diabetes, as well as in reversing insulin resistance in healthy people. This research study aimed to investigate the effect of magnesium intake in overweight and insulin-resistant people, as well as in normal people.

Methodology

  • The study was a done in single center, double-blind, randomized and placebo-controlled.
  • Magnesium-aspartate-hydrochloride was provided to 52 subjects aged between 30 and 70 years, for a period of six months.
  • Insulin sensitivity indices were calculated from an oral glucose tolerance test.
  • Other parameters like blood pressure, cholesterol level, energy expenditure, and intracellular, extracellular, and free magnesium concentrations were determined.

Results

  • A major improvement in insulin sensitivity was observed on use of magnesium supplement in obese, insulin-resistant subjects.
  • Fasting plasma glucose levels were notably reduced in the magnesium group. Additionally, the diastolic blood pressure was reduced in the magnesium group.
  • The findings from this research are consistent with other research done on patients with type 2 diabetes or insulin-resistant subjects without diabetes
  • Insulin resistance decreased, in spite of normal magnesium concentration in the blood, similar to other studies on patients with below-normal magnesium levels.

Next steps/Shortcomings
The chemical mechanism behind the observed improvement in insulin resistance, as an effect of oral magnesium supplement, has not been yet detected, although several hypotheses have been proposed. This could be a subject of research in future. There was a marginal difference between the patients who were treated with magnesium supplement and those with controls. A study involving more subjects might yield more concrete results.

Conclusion
Of the three tests conducted to test for insulin sensitivity, two showed a major decrease in insulin resistance upon oral intake of magnesium. The present study involved participants with normal magnesium levels, who showed a moderate 20 percent decrease in insulin resistance after treatment with oral magnesium. Comparatively, participants with low magnesium levels in previous studies showed a 51 percent reduction in insulin resistance with oral magnesium supplementation. This implies that magnesium’s effects on increasing insulin sensitivity are heightened when blood levels of magnesium are low. Magnesium supplementation may be more effective in improving insulin resistance than a strict lifestyle modification. This study further emphasizes the role of magnesium in controlling glucose levels in non-diabetic patients as well. The researchers of this study hypothesize that a marginal deficit of magnesium negatively impacts insulin action. This work highlights the preventive role of magnesium intake by food for people at risk of metabolic syndrome.

For More Information:
Oral Magnesium Reduces Insulin Resistance in Non-Diabetic People
Diabetes, Obesity and Metabolism, 2011
By F. C. Mooren; K Krüger
From the Justus-Liebig-University, Giessen, Germany

*FYI Living Lab Reports Are Summaries of the Original Research.