Magnesium Improves Bone Strength

By Hans R. Larsen MSc ChE – http://www.afibbers.org/magnesium.html
MEMPHIS, TENNESSEE. Many atrial fibrillation patients have found magnesium supplementation highly beneficial in preventing ectopic beats (PACs and PVCs) and even afib episodes. Now there is evidence that an adequate daily magnesium intake also materially improves the density of skeletal bone and helps prevent osteoporosis and hip fractures. Researchers at the University of Tennessee measured bone mineral density (BMD) in a group of older men and women (black and white between the ages of 70-79 years). The 2038 participants were enrolled in the Health, Aging and Body Composition Study initiated in 1997. The researchers also determined the participants’ daily intake of magnesium, calcium, potassium, vitamin D, and vitamin C. Less than 26% of the study group met the Recommended Daily Allowance (RDA) for magnesium (320 mg/day for women and 420 mg/day for men over the age of 70 years). Twenty-five per cent took a magnesium supplement providing an average of 83 mg/day of elemental magnesium. Black men and women had a significantly higher BMD than did white persons and did not benefit from higher magnesium intake.

White women with the highest magnesium intake had a significantly higher BMD than women with lower intakes with an increase in daily intake from 220 mg/day to 320 mg/day corresponding to an increase of 0.020 g/cm2 in whole body BMD (after adjusting for other relevant variables). For white men, an increase from 320 mg/day to 420 mg/day corresponded to an increase of 0.010 g/cm2 in whole body BMD. These increases are roughly equivalent to those that would result from increasing daily calcium intake by about 400 mg. The researchers speculate that the beneficial effects of an increased magnesium intake on bone density may be due to one or more of the following factors:

* Improved synthesis of vitamin D with subsequent suppression of parathyroid hormone function.
* Increased alkalinity of a diet high in magnesium and lower net acid production.
* Substitution of calcium with magnesium in the formulation of bone hydroxyapatite, resulting in greater structural strength. NOTE: Strontium may have a similar effect.

The researchers conclude that a higher magnesium intake through dietary change or supplementation may provide an additional strategy for preventing osteoporosis.

Ryder, KM, et al. Magnesium intake from food and supplements is associated with bone mineral density in healthy older white subjects. Journal of the American Geriatrics Society, Vol. 53, November 2005, pp. 1875-80