Magnesium Supplementation and Bone Mineral Density

The effects of magnesium supplementation in diets with different calcium levels on the bone status and bone metabolism in growing female rats.

Abstract:

Previous studies have revealed that magnesium (Mg) plays a significant role in bone health; however, few studies have investigated the effects of Mg supplementation in diets with different calcium (Ca) levels on the bone status and bone metabolism in a growing stage. In this present study, we tested the effects of Mg supplementation on bone status in growing female rats, relative to Ca intake levels. A total of 40 Sprague-Dawley female rats aged 6 weeks were divided into the following four groups and fed for 12 weeks as indicated: (1) LCaAMg: low Ca (Ca, 0.1 % of total diet) and adequate Mg (Mg, 0.05 % of total diet), (2) LCaHMg: low Ca and high Mg ( Mg, 0.1 % of total diet), (3) ACaAMg: adequate Ca (Ca, 0.5 % of total diet) and adequate Mg, and (4) ACaHMg: adequate Ca and high Mg. Our results showed that Mg supplementation with the adequate Ca diet significantly increased the bone mineral contents, bone size (bone area and bone thickness), and bone mineral density of femur or tibia by improving bone metabolism without changing Ca absorption. Mg supplementation significantly increased the serum osteocalcin in the adequate-Ca-diet group (p < 0.05), while the Mg supplementation significantly decreased the serum level of C-telopeptide cross-links of type I collagen in the adequate-Ca-diet group (p < 0.001). This study suggests that Mg supplementation with adequate Ca intake in the growing stage may increase the bone mineral density and bone size by improving bone metabolism.

Source:

Biol Trace Elem Res. 2013 Dec;155(3):431-8. doi: 10.1007/s12011-013-9798-1. Epub 2013 Sep 18.
Bae YJ, Kim MH.

Expert Commentary:

“In this study, the effects of Magnesium supplementation on different calcium levels in the diet was tested on four groups of rats. In the grand tradition of the body always leaning towards homeostasis, the group given magnesium supplementation with an adequate Calcium diet significantly increased the bone mineral contents, bone size (bone area and bone thickness), and bone mineral density of femur or tibia by improving bone metabolism without changing Calcium absorption. This indicates that adequate calcium and magnesium together create an optimum environment for bone health.”

Carolyn Dean, MD, ND