October 23, 2013
Study: Vitamin D Unnecessary to Prevent Osteoporosis in Healthy Adults

Aukland, New Zealand—The vitamin D supplements taken daily by many adults to prevent osteoporosis are unnecessary and provide them little or no benefit.

That’s according to a meta-analysis published recently in The Lancet by researchers from the University of Auckland.

“Most healthy adults do not need vitamin D supplements,” asserted study leader Ian Reid, BSc, MBChB, MD, who instead suggested that low-dose vitamin D supplements only be used by “individuals who are likely to be deficient.”

Background in the article noted that, even though data suggests that vitamin D supplementation without coadministration of calcium has little effect on fracture prevention, “almost half of older adults (older than 50 years) continue to use these supplements.”

For the study, Reid and his colleagues analyzed 23 studies that met the inclusion criteria; those involved 4,082 participants—92% women with an average age of 59 years—over a mean duration of 23.5 months.

“Results of our meta-analysis showed a small benefit at the femoral neck (weighted mean difference 0·8%, 95% CI 0·2—1·4) with heterogeneity among trials (I2=67%, p< 0·00027),” the authors write. “No effect at any other site was reported, including the total hip. We recorded a bias toward positive results at the femoral neck and total hip.”

The authors conclude, “This systematic review provides very little evidence of an overall benefit of vitamin D supplementation on bone density…Continuing widespread use of vitamin D for osteoporosis prevention in community-dwelling adults without specific risk factors for vitamin D deficiency seems to be inappropriate.”

Writing in a linked comment, Clifford J Rosen, MD, from the Maine Medical Research Institute in Scarborough, ME, agrees: “Supplementation to prevent osteoporosis in healthy adults is not warranted. However, maintenance of vitamin D stores in the elderly combined with sufficient dietary calcium intake (800–1200 mg per day) remains an effective approach for prevention of hip fractures.”

Rosen adds that the “Investigators conclude that widespread vitamin D prophylaxis in healthy community-dwelling adults to prevent osteoporosis is unwarranted. How can these surprising findings be reconciled with clinical practice and public health strategies to prevent osteoporosis?” Among other explanations, he points out that bone mineral density changes in the older age group are only a modest predictor of subsequent fractures.

U.S. Pharmacist Social Connect