Vitamin D, Fall Prevention & Bone Health
A Randomized Clinical Trial
A large number of studies have been published regarding vitamin D, especially of late. Research has looked at the connection between vitamin D and all-cause mortality, cognitive ability, mood, respiratory infection, cancer, and more. Yet most of this research has been flawed, in one way or another; a problem that even some of the vitamin D researchers themselves have written about1.
Problems with vitamin D research have ranged from issues like small sample sizes and poor testing methods to poor experimental design. One of the most important problems with most areas of vitamin D research is a lack of trial studies; major articles regarding vitamin D and all-cause mortality, mood, etc., are usually observational. There is a great need for randomized clinical trials in vitamin D research, which would provide a better idea of the effects of supplementation and do a better job of controlling for unknown variables than any observational study.
JAMA published a research article on vitamin D this year that was free of most of those problems. The article featured the results of a randomized clinical trial looking at the relationship between exercise, vitamin D, and falls in elderly women. Groups that received vitamin D received one 800 IU pill per day of vitamin D3, a much more useful supplementation regimen for trials than many other studies have utilized. The study also had a much larger number of participants than many other vitamin D studies — over 100 people per group. The major downside to this study is the lack of useful data regarding vitamin D blood levels, rather than just supplementation. While the medical community is in desperate need of good data on vitamin D supplementation, it is the vitamin D blood level that predicts effects, not the supplementation. Moreover, though the sample population did not take other vitamin D supplement capsules, they consumed vitamin D fortified foods, and seem to have had higher vitamin D levels than many other populations.
The researchers divided their participants into four groups: one receiving a placebo, one receiving the vitamin D supplement, one with an exercise regimen, and one that both exercised and received the vitamin D supplement. The researchers did not find that vitamin D had a statistically significant effect on the rate of falls or injurious falls, though the data does suggest a slight decrease in falls and injurious falls compared to the non-vitamin D groups. They did find a significant improvement, however, in the bone health of supplemented groups. Vitamin D, and especially vitamin D supplementation in tandem with exercise, had a positive effect on bone mineral density in comparison to the other groups. This is especially of interest when you consider that these patients already were at vitamin D blood serum levels not considered deficient for the purposes of bone health.
You can follow the link below or use the citation to find the JAMA article.
Uusi-Rasi, K., Patil, R., Karinkanta, S., Kannus, P., Tokola, K., Lamberg-Allardt, C., & Sievänen, H. (2015). Exercise and vitamin D in fall prevention among older women: a randomized clinical trial. JAMA internal medicine, 175(5), 703-711.