Muscle Strength Linked to Magnesium in Older Adults

Summary By Hans R. Larsen MSc ChE
PALERMO, ITALY. Magnesium is central to human health as it plays a role in a wide range of activities on the cellular level. A deficiency can lead to muscle weakness, fatigue and insomnia. This nutrient may therefore be essential for maintaining muscle strength throughout life. Evidence from athletes supports a role for magnesium in avoiding damage to muscle cells. Muscle mass and function can be compromised in older age, a condition known as sarcopenia. Researchers from the University of Palermo investigated the relationship between sarcopenia and magnesium status. They analyzed data from the Italian InCHIANTI (aging in the Chianti area) study. Data on muscle performance and serum magnesium, gathered at the same time, were available for 1,138 healthy men and women. Mean age was 67 years and the participants were considered representative of the general population. Magnesium status was found to be significantly related to each of the measures of muscle strength – grip strength, lower-leg muscle power, knee rotation, and ankle strength. The link, found in both men and women, remained “highly significant” once the results were adjusted for factors including age, sex, body mass index, and levels of several other nutrients. In case the link was due to magnesium deficiency among certain participants, the analysis was repeated excluding individuals identified as deficient and a highly significant relationship was still observed. The researchers suggest that the explanation may lie in the importance of magnesium to metabolism, or the increased free radical production and proinflammatory effects of low magnesium. They conclude that serum magnesium is significantly, independently, and strongly linked to muscle performance in older people. Measurement of serum magnesium should be part of routine physical check-ups, they believe, but they add that it is not fully clear whether magnesium supplementation improves muscle function. Magnesium is found in green vegetables such as spinach, nuts (especially almonds), seeds, and some whole grains. Excessive intake can interfere with calcium absorption.

Dominguez, L. J. et al. Magnesium and muscle performance in older persons: the InCHIANTI study. The American Journal of Clinical Nutrition, Vol. 84, August 2006, pp. 419-26