NPA, CRN: USPSTF’s vitamin D, calcium advice could be harmful to women at risk of fractures
The USPSTF stated it had concluded that “the current evidence is insufficient to assess the balance of the benefits and harms of daily supplementation with greater than 400 IU of vitamin D3 and greater than 1000 mg of calcium for the primary prevention of fractures in non-institutionalized postmenopausal women.
“The USPSTF recommends against daily supplementation with 400 IU or less of vitamin D3 and 1000 mg or less of calcium for the primary prevention of fractures in non-institutionalized postmenopausal women.”
Dr Cara Welch, senior vice president of scientific and regulatory affairs for the NPA, said the taskforce’s recommendations conflict with the recommendations of the Institute of Medicine.
Taylor Wallace, PhD, senior director, scientific and regulatory affairs for the CRN said: “These recommendations fail to recognize the well-established role of calcium and vitamin D in maintaining bone health.
“If these recommendations are taken to heart, or misconstrued as general recommendations against calcium and vitamin D, consumers could be compromising their bone health and missing out on important other benefits from these nutrients. The bottom line: calcium and vitamin D are vital to staying healthy.”
Inconclusive evidence?
“Vitamin D and calcium are known to play an important role in maintaining health, including bone health. However, despite the large number of studies done there are few conclusive answers about the ability of vitamin D and calcium supplements to prevent fractures,” said Task Force member and chair Virginia Moyer, MD.
“The Task Force has determined the evidence is inconclusive that higher doses of vitamin D and calcium supplements are effective in preventing fractures in postmenopausal women. The evidence was also inconclusive for fracture prevention in men and premenopausal women. What we do know is that doses less than or equal to 400 IU of vitamin D (or 1000 mg of calcium) are not effective at preventing fractures in postmenopausal women.”
Fellow Task Force member Jessica Herzstein, MD, added: “Vitamin D plays a role in a wide range of general health functions, and there appears to be minimal harms in taking vitamin D supplements. Clinicians and patients may take this into consideration when determining whether to recommend or take vitamin D for general health.”
Conflicts
“The Natural Products Association believes that dietary supplementation is both safe and effective for anyone who isn’t getting enough calcium and vitamin D from their diet,” said Dr Welch.
“These nutrients have been shown to support bone health and it’s important that consumers get the recommended levels of both. If diet alone isn’t enough, then dietary supplements can help with getting these vital nutrients.
Dr Welch added that the Task Force's statement that "supplementation has not been proven beneficial and carries a small risk" conflicts with the recommendation of the Institute of Medicine, "which took into account nearly 1,000 published studies that confirm the role of calcium and vitamin D supplements in promoting bone health.
“The statement by the task force is contradicted by current research and may prove harmful to women at risk of fractures. Studies continue to show the beneficial effects of calcium and vitamin D supplements. As always, NPA recommends that consumers discuss their nutritional needs with their health care professional.”
WHI
CRN’s Dr Wallace noted that the USPSTF’s meta-analysis was heavily reliant on the Women’s Health Initiative (WHI), the largest randomized, double-blind, placebo-controlled clinical trial of these nutrients involving 36,282 postmenopausal women in the US. The women were randomly assigned to receive to 1,000 mg elemental calcium carbonate plus 400 IU of vitamin D3 daily or placebo for an average if seven years.
The initial analysis of the data, published in 2006 in the New England Journal of Medicine (Vol. 354, pp. 669-683), concluded: “Among healthy postmenopausal women, calcium with vitamin D supplementation resulted in a small but significant improvement in hip bone density, and did not significantly reduce hip fracture.”
However, in the 59% of the participants who actually adhered to the supplementation program (assuming 80% or more compliance with taking the supplements) the number of fractures was significantly lower, leading this publication to run with the headline: Calcium/ vitamin D supplements good for bones – if you take them (NutraIngredients-USA, Feb 16, 2006).
However, a recent re-analysis of the WHI data revealed a 38% reduction in hip fracture and no increased incidence of kidney stone development for women who strictly adhered to the calcium/vitamin D protocol. The results of this latest study were not included in the USPSTF meta-analysis, said Dr Wallace, who added that the results of this latest re-analysis were “extremely compelling.”