During cold season, many people take vitamin D supplements to help stave off sickness. While scientists have yet to prove that vitamin D supplements can prevent the common cold (sometimes referred to as an "upper respiratory tract infection"), some research shows that having higher a higher vitamin D level may correlate with a reduced risk of catching a cold.
Health Benefits of Vitamin D for the Common Cold
To date, few studies have tested the effectiveness of vitamin D supplements for prevention of the common cold. What's more, the existing research has yielded mixed results. For instance, a 2009 study published in Epidemiology and Infection found that vitamin D failed to decrease the incidence and severity of upper respiratory tract infections over a three-month period. In an experiment involving 162 adults, those given 2,000 IU of vitamin D in supplement form daily were no less likely to suffer colds than those assigned to a placebo.
However, a population study published in the Archives of Internal Medicine the same year suggests that maintaining optimal vitamin D levels may help fend off colds. Looking at data on 18,883 people, researchers found that those with the lowest vitamin D levels were about 40 percent more likely to report a recent respiratory infection (compared to those with the highest vitamin D levels). The study detected a particularly strong link between low vitamin D levels and respiratory infection risk among participants with a history of respiratory disorders (such as asthma).
Using Vitamin D for Cold Prevention
The currently available data does not support taking vitamin D supplements for this purpose, although this is an area of ongoing research. Maintaining optimal levels of vitamin D may offer a number of other health benefits. For instance, optimal vitamin D levels are important for keeping your bones strong and protecting against osteoporosis. For more help in fighting off the common cold, make sure to wash your hands frequently, follow a balanced diet, exercise regularly, and get sufficient sleep.
If you're considering the use of vitamin D supplements for cold prevention, or if you're concerned that your levels of vitamin D may be low, consult your primary care provider.
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