Spoiler: It’s not vitamin C
How many times have you popped a vitamin C tablet in hopes of fighting off a cold? Turns out, you may have been reaching for the wrong vitamin
Taking vitamin D may help prevent sickness, according to researchers from Queen Mary University of London. That’s what they concluded after they crunched the numbers on 25 previous studies including 11,000 participants, and discovered that vitamin D supplementation reduced the risk of contracting a respiratory infection by 12 percent. (These are the 6 best supplements for men.)
So how does the sunshine vitamin ward off colds, bronchitis, and other respiratory ills? It’s all about boosting your cellular defenses, says lead study author Adrian Martineau, Ph.D.
"Vitamin D supports the production of ‘antimicrobial peptides’ by the immune system,” Martineau says. “These are natural, antibiotic-like substances (found in white blood cells and the lining of the lung) that can kill bacteria and viruses responsible for respiratory infections.”
Whether or not the body-boosting effects of vitamin D supplementation apply to actually treating your cold is still unknown. According to Martineau, clinical trials are currently testing this idea but the results aren’t conclusive yet. (These are the top 10 things that can happen when you’re lacking vitamin D.)
Still, the results of this study do add further support to just how important getting enough vitamin D really is—especially in winter months where we scarcely see the sun. Besides warding off sickness, vitamin D also helps your body absorb calcium, and may also help fight diabetes.
Reaching for vitamin D-rich food like tuna, salmon and mushrooms can help boost your daily intake, but it might not be enough. The National Institutes of Health currently recommends 600 IU (or 15 micrograms) of daily vitamin D for men between 19- 50 years old.
“That’s hard to get from the sun—especially in winter and spring—and diet,” says Martineau. “The logical conclusion is that one would have to get it from a supplement.”
Now, if you eat a ton of tuna and salmon, drink vitamin D fortified milk, or spend a lot of time in the sun year round, you might not need a supplement. But the results of the study found that taking one didn’t seem to have any negative health effects on participants, either. So it’s worth checking with your doctor to see if you should up your daily dose.