By Jeremy Appleton, ND, CNS
Healthnotes Newswire (April 20, 2006)—Long-term supplementation with a vitamin D–calcium combination reduced the risk of falls in older women, according to the Archives of Internal Medicine (2006;166:424–30).
Participants were randomly assigned to receive 700 IU per day of vitamin D3 plus 500 mg per day of calcium (as calcium citrate malate) or placebo for three years. Of the 445 volunteers who began the study, 389 attended the three-year follow-up visit, and 318 were still taking the supplements. Originally designed to examine the effect of the vitamin–mineral combination on bone mineral density, the study also looked at a person’s risk of falling at least once during the follow-up period.
Supplementing with vitamin D–calcium reduced the odds of falling by 46% among most women and by as much as 65% in less active women. This benefit was further enhanced among less active women who continued to take the supplements for the entire three years; in that group there was a 74% fall reduction. Although men did not receive a statistically significant benefit, there was a trend toward improvement among less active men who stayed on treatment to the end of the study.
While it is well known that calcium is required for muscle function, it is not well appreciated that vitamin D is also required for muscle function. Several studies have indicated a positive association between blood levels of vitamin D and lower extremity strength and function in older people. But how could taking a vitamin D supplement prevent falls? Muscle tissue contains vitamin D receptors that promote muscle strength and have been shown to decline in number with age. In fact, muscle weakness—a major risk factor for falls in the elderly—is a prominent sign of vitamin D deficiency. In addition, vitamin D plays a role in the normal functioning of the nervous system, and vitamin D deficiency leads to poor balance.
The findings fit well with the results of the original study, which showed a 60% reduction of osteoporotic fractures with vitamin D–calcium compared with placebo, since many such fractures result from falling. Consistent with the present study, most of the fractures occurred in women. The benefits obtained by this simple, cost-effective intervention are comparable to or greater than those of more expensive and time-consuming interventions, such as medication adjustments, occupational therapy, and exercise programs.
Jeremy Appleton, ND, CNS, is a licensed naturopathic physician, certified nutrition specialist, and published author. Dr. Appleton was the Nutrition Department Chair at the National College of Naturopathic Medicine, has served on the faculty at Bastyr University of Natural Health Sciences, and is a former Healthnotes Senior Science Editor and a founding contributor to Healthnotes Newswire. He has worked extensively in scientific and regulatory affairs in the supplement industry and is now a consultant through his company Praxis Natural Products Consulting and Wellness Services.