Approximately 70 percent of people get at least one respiratory infection, such as the common cold, bronchitis, pneumonia, and sinus and ear infection, in a year. However, a large review and meta-analysis of randomized, controlled studies shows that vitamin D supplements can cut down the amount of people suffering these infections by 12 percent. The study was recently published in the British Medical Journal.
Researchers analyzed data from 25 clinical trials, conducted in 14 countries, which included over 11,000 participants of all ages. They conclude that daily or weekly vitamin D supplements can protect against acute respiratory tract infections. The greatest benefit was shown in those who were deficient in vitamin D.
Most of the vitamin D needed by humans comes from sunlight. Winter and cold weather months may be a good time to add a supplement to aid in preventing these illnesses. Speak to your health care provider about your specific situation.
Source: Martineau A, Jolliffe D, Hooper R, et al. Vitamin D supplementation to prevent acute respiratory tract infections: systematic review and meta-analysis of individual participant data. BMJ, 2017;356:i6583.