Winter Sunshine

Vitamin D: The Panacea That Isn’t

It’s hard to argue with something dubbed “the sunshine vitamin” – more specifically, vitamin D. It’s been generating headlines and controversy for years now. The vitamin D fan club described it like a panacea, good for preventing bone fractures (of course), but also ills ranging from infections to diabetes and cancer. Because of its association with better immune function, it got a boost during the height of the COVID-19 pandemic, with both Tony Fauci and the ex-President taking it. It retrospect, it was at best a dud for preventing COVID. Vaccines and other preventive measures do far more.

But the toughest blow for the fan club came this week from a randomized clinical trial published in the New England Journal of Medicine. It showed in convincing terms that vitamin D does not lower the risk of bone fractures for generally healthy midlife and older adults. Commenting in an editorial alongside this study, Steven Cummings and Clifford Rosen called this a decisive verdict:

“Adding those findings to previous reports from VITAL and other trials showing the lack of an effect for preventing numerous conditions suggests that providers should stop screening for 25-hydroxyvitamin D levels or recommending vitamin D supplements, and people should stop taking vitamin D supplements to prevent major diseases or extend life.”

Seduced by the Magic of Vitamins?

If you want to understand the seductiveness of promising that a vitamin can protect you from a health threat, look no further than the latest sales stats for these supplements. Even at this late stage of the pandemic, when we have prevention tools that actually work, sales for vitamin D and “immune support” supplements are still strong.

Though vitamin D is no panacea, the desire to believe in it is potent. Despite the latest disappointing results, we’re still hearing various reasons for sticking with it. Mayo Clinic professor Sundeep Khosla told the New York Times he intends to keep recommending vitamin D for patients with osteoporosis because it will do little harm and may yet prove to have benefits. He goes further and says:

“I will still tell my family and friends who don’t have osteoporosis to take a multivitamin a day to make sure they don’t get vitamin D deficient.”

In full disclosure, we too follow this advice. It has the appeal of a talisman, even though we know the health benefit may be negligible.

Click here for the study, here for the editorial, and here for further reporting.

Winter Sunshine, painting by Ethel Léontine Gabain / WikiArt

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July 30, 2022