Study: Vitamin D helps maintain bone density

CHICAGO — In a clinical trial that explored the effectiveness of exercise training and vitamin D supplementation for reducing falls in older women, neither intervention affected the overall rate of falls, according to an article published online Monday by JAMA Internal Medicine. However, vitamin D did help to maintain bone density in the femoral neck (a segment of the femur most likely to break with osteoporosis) and increased tibial trabecular density in the shinbone. 

 

Only exercise improved muscle strength and balance, while vitamin D did not enhance the effects of exercise on physical functioning.

 

“Given the fact that fall risk is multifactorial, exercise may be the most effective and feasible strategy for preventing injurious falls in community-dwelling older adults replete with vitamin D," said Kirsti Uusi-Rasi, researcher with the UKK Institute for Health Promotion Research, Tampere, Finland. "Herein, vitamin D increased bone density slightly, and exercise improved physical functioning. While neither treatment reduced the rate of falling, injurious falls more than halved among exercisers with or without vitamin D. Our participants were vitamin D replete, with sufficient calcium intake. Future research is needed to elaborate the role of vitamin D to enhance physical functioning in elderly women.” 

 

"This new study confirms the established role of vitamin D for bone health, but there are many other beneficial reasons for people to supplement with vitamin D," said Duffy MacKay, SVP scientific and regulatory affairs for the Council for Responsible Nutrition. "Other studies have pointed to a role for vitamin D in helping with cognitive function and reducing the risk of heart disease, diabetes and other chronic diseases; however, it is important to manage expectations for vitamin D’s role in isolation and to remember that optimal nutrition is just one component of many needed to prevent chronic disease."

 

Falls are the leading cause of unintentional injuries and fractures in older adults. However, reviews of clinical trials on the role of vitamin D in reducing falls and fractures in community-dwelling older adults and in improving physical functioning have been inconclusive, according to the study background.

 

In an accompanying commentary to the study, the commentary authors noted that although this new study didn’t find benefit for vitamin D in preventing falls among older women, updating the recent USPSTF meta-analysis to include this trial " ... does not change the overall conclusion that vitamin D remains associated with an 11% decreased risk of falls." 

 

The authors pointed to some of the possible confounding factors to consider with this positive conclusion for vitamin D, including whether calcium was also administered. Further, the commentary authors reminded doctors that given its low cost and low risk, vitamin D should remain in the physician’s collection of resources while more research continues. "As those authors pointed out, taking a person’s vitamin D status into account may be useful in determining recommendations for helping prevent falls," MacKay said.