New Guidelines: No Daily Vitamin D/Calcium Postmenopause

A new US Preventive Services Task Force (USPSTF) recommendation statement has concluded that the evidence is insufficient to support the use of vitamin D and calcium supplementation to prevent fractures among community-dwelling men and premenopausal women. However, the task force did find sufficient evidence to recommend against daily vitamin D and calcium supplements for the primary prevention of fractures in postmenopausal women.

Virginia A. Moyer, MD, MPH, from the Baylor College of Medicine in Houston, Texas, published the recommendation statement on behalf of the USPSTS online February 26 in the Annals of Internal Medicine.

In its statement, the task force mentions that physicians should use more than evidence alone in their decision-making. "Clinicians should understand the evidence but individualize decision making to the specific patient or situation," Dr. Moyer writes. "Similarly, the USPSTF notes that policy and coverage decisions involve considerations in addition to the evidence of clinical benefits and harms."

In its assessment, the USPSTF performed 2 systemic reviews and a meta-analysis of the effects of vitamin D supplementation with or without calcium on bone health among community-dwelling adults. In pooled trials, vitamin D and calcium supplementation had no effect on the frequency of bone fractures (pooled relative risk, 0.89; 95% confidence interval [CI], 0.76 - 1.04).

In addition, no evidence of an effect of vitamin D supplementation alone on fracture risk was observed (pooled relative risk, 1.03; 95% CI, 0.84 - 1.26). A meta-analysis of people aged 65 years or older determined that fracture risk may be reduced by supplementation with higher doses of vitamin D (≥800 IU daily ), but these effects were not significant in subgroup analyses.

The Women's Health Initiative (WHI) trial of 36,282 healthy postmenopausal women reported a slightly increased risk for nephrolithiasis associated with vitamin D and calcium supplementation (hazard ratio, 1.17; 95% CI, 1.02 - 1.34), with a number needed to harm of 273. The task force concluded that the magnitude of this harm was small.

"Except for postmenopausal women, there is inadequate evidence to estimate the benefits of vitamin D or calcium supplementation to prevent fractures in noninstitutionalized adults," Dr. Moyer writes. "Due to the lack of effect on fracture incidence and the increased incidence of nephrolithiasis in the intervention group of the WHI trial, the USPSTF concludes with moderate certainty that daily supplementation with 400 IU of vitamin D₃ and 1000 mg of calcium has no net benefit for the primary prevention of fractures in noninstitutionalized, postmenopausal women."

In a related editorial, Marian Nestle, PhD, MPH, from New York University in New York City, and Malden C. Nesheim, PhD, from Cornell University in Ithaca, New York, note the lack of evidence supporting vitamin D supplementation.

"A previous attempt to sort through the various claims for vitamin D noted an urgent need for further research to answer fundamental questions about the risks and benefits of sun exposure, fortification, and supplements, and the hormone's role in body functions beyond bone mineralization," Dr. Nestle and Dr. Nesheim write. "While we wait for the results of further research, the USPSTF's cautious, evidence-based advice should encourage clinicians to think carefully before advising calcium and vitamin D supplementation for healthy individuals."

Dr. Moyer has disclosed no relevant financial relationships. Dr. Nestle received payment for lectures from the Steven Barclay Agency, royalties for published books from UC Press, and payments for travel accommodations from various universities and organizations. Dr. Nesheim received royalties from UC Press for published books.

Ann Intern Med. Published online February 25, 2013.