Vitamin D supplements have long been touted as offering myriad health benefits, including protecting against cognitive decline, cancer, and bone fractures, and even increasing one’s lifespan. But research published today (July 28) in The New England Journal of Medicine (NEJM) concludes that high-dose vitamin D pills offer no protection against bone fractures or osteoporosis in middle-aged and older adults, regardless of factors such as sex, age, and race.
“The takeaway is that in general, people shouldn’t be popping vitamins left and right and if you’re trying to prevent fractures, vitamin D alone is not enough,” Columbia University Medical Center endocrinologist Ethel Siris tells NBC.
The research comes in the form of an ancillary study to the Vitamin D and Omega-3 Trial (VITAL), which recruited nearly 26,000 participants—all either men over the age of 50 or women over 55 from the US—to measure the effects of vitamin D supplementation against a placebo on several health conditions. As The New York Times reports, bone fractures and osteoporosis now join the list of several other vitamin D supplement use cases that the VITAL study has debunked. For example, earlier analyses of the data found that the supplements don’t protect against developing cancer or cardiovascular disease, falls, cognitive decline, migraines, stroke, macular degeneration, or joint pain—nor did it reduce body weight or BMI.
Even though the supplements are taken by millions of Americans, according to the Times, some experts who reviewed the data now say it’s not worthwhile to do so without specific reason, such as an extreme deficit.
“Providers should stop screening for 25-hydroxyvitamin D levels or recommending vitamin D supplements and people should stop taking vitamin D supplements in order to prevent major diseases or extend life,” California Pacific Medical Center Research Institute scientist Steven Cummings and NEJM editor Clifford Rosen, also a senior scientist at the Maine Medical Research Institute, write in an accompanying NEJM editorial.
As controversy surrounding the flawed research that showed alleged benefits of the Mediterranean diet has shown, conducting nutrition research that’s robust and accurate is particularly difficult due to the countless other variables in a person’s lifestyle that can influence health outcomes and the difficulty of ensuring they stick to a particular diet or accurately report what they consumed in the past. While the VITAL study is logistically simpler—placebo-controlled, blinded analyses of the outcomes of a single supplement are easier to conduct than those that involve a person’s entire diet—it also had some limitations that leave some experts saying they may still recommend vitamin D after all.
For example, the VITAL study looked at people who were more or less in good health; it didn’t include those who already had osteoporosis or severe vitamin D disorders, notes the Associated Press.
“Simply giving people vitamin D doesn’t prevent fractures,” Siris tells NBC. “But adequacy of calcium and vitamin D intake, in my opinion, remains a necessary part of the management of people with osteoporosis.”