Magnesium linked to lower weight, waist size and blood sugar: Mexican study

Data from 1,573 people aged between 20 and 65 without diabetes indicated that for every 10 mg per 1000 kcal/day increase in magnesium intake, average BMI was 0.72% lower, while waist circumference (WC) was 0.5 cm smaller.

It is important to stress that the data shows a correlation and not causation, and more studies – including interventional studies – are needed to further explore the association.

“To the best of our knowledge, this is the first study to describe the prevalence of inadequate intake of nutrients with antioxidant function by BMI, WC and serum glucose categories and to evaluate the association between its intake and markers of adiposity and glucose metabolism in this population,” ​wrote researchers from Mexico’s National Institute of Public Health, Iowa State University, and the University of Brasilia.

“These results highlight the importance of an adequate dietary magnesium intake”​

‘Necessary for over 300 biochemical reactions’​

The results add to an ever growing body of science supporting the potential health benefits of the mineral. The National Institutes of Health (NIH) lists magnesium as being necessary for more than 300 biochemical reactions in the body, from helping maintain normal muscle and nerve function, to keeping heart rhythm steady, supporting a healthy immune system, and keeping bones strong. The mineral is also needed for blood sugar management and healthy blood pressure. 

The science and positive regulatory decisions have led to increased interest from consumers in magnesium and this has led to increasing sales. And with 70-80% of the US population not meeting their recommended intakes of magnesium, the market is expected to continue to grow. Indeed, some industry experts are predicting​ that magnesium sales in the nutrition market will surpass calcium by 2020.

Study details​

Using a method developed by the US Department of Agriculture and adapted to the Mexican context, the researchers analyzed dietary data from over 1,500 people. Diets were assessed using 24-hour dietary recall, and intakes of vitamins A, C, E and magnesium were estimated using Mexican National Institute of Public Health food composition tables.

The results showed that there were no associations found for vitamins A, C, E, but higher magnesium intakes were associated with lower BMI, waist circumference, and serum glucose concentrations, reported the researchers.

“Consistent with our findings, other studies have also reported an inverse association between magnesium intake and markers of adiposity,” ​they wrote. “The mechanism that explains this association is not yet fully understood. While one of the functions of magnesium is its antioxidant effect through enzymatic mechanisms, the role of [oxidative stress] in the development of obesity is still unclear.”​

The researchers added that other studies have found that lower magnesium intakes may be linked with an increased risk of insulin resistance.

“[M]agnesium may have an effect on adiposity and serum glucose concentrations through other mechanisms not involved in [oxidative stress], since in addition to its antioxidant function, it is also involved in energy metabolism.”​

Source: Nutrition Journal​​
17​:114, doi: 10.1186/s12937-018-0422-2​
“Higher dietary magnesium intake is associated with lower body mass index, waist circumference and serum glucose in Mexican adults”​
Authors: A. Castellanos-Gutiérrez, et al.