Study Finds Vitamin D May Do Nothing To Prevent Common Colds
Contrary to conventional wisdom, a new study finds a dose of Vitamin D--long considered a surefire way to prevent a common cold--does nothing to stave off colds or other forms of upper respiratory tract infections.
The study, published this week in the Journal of the American Medical Association, included 322 healthy adults in New Zealand and found that those who took large monthly doses of vitamin D developed just as many infections over an 18-month period as their counterparts who took a placebo.
According to the study, the people in the vitamin D group came down with an average of 3.7 bouts of cold or flu, compared to 3.8 in the placebo group -- a statistically negligible difference.
The researchers also found no evidence that vitamin D had any measurable impact on the severity of symptoms, their duration (about 12 days per episode in each group), or the number of workdays missed.
"The main finding from this study is that a monthly dose of 100,000 international units (IU) of vitamin D3 in healthy adults did not significantly reduce the incidence or severity of upper respiratory tract infections (URTIs). This result remained unchanged when the analysis included winter season or baseline [vitamin D] levels," the authors wrote.
In an accompanying editorial, Dr. Jeffrey Linder, internal medicine specialist and assistant professor at Harvard Medical School suggested that Vitamin D can probably be placed alongside many other popular cold-and-flu remedies, like vitamin C, zinc, echinacea, and garlic, whose supposed benefits have not stood up to clinical trials.
"Colds are inevitable. We all get them, and they make us all miserable, and I don't think we're going to come up with a way around that," Linder explained. "Besides eating a balanced diet with lots of vitamins and minerals, and exercising, and generally living a healthy life, it's unlikely that we're going to find one single pill or cure that's going to prevent them or lessen their severity."
[image via Getty]