5 Immunity-Boosting Foods & Nutrients (Page 5)

4. Vitamin D

In a study published recently in the American Journal of Clinical Nutrition, children who took daily vitamin D supplements (1,200 IU) were 40 percent less likely to get a common flu virus than kids who took a placebo. Laboratory studies indicate that the nutrient may help immune cells identify and destroy bacteria and viruses that make us sick, says Adit Ginde, M.D., M.P.H., a public health researcher at the University of Colorado School of Medicine in Denver. Since the majority of Americans don’t get enough vitamin D, most experts recommend a D supplement. You can also get it (in small doses) from fatty fish, such as salmon, and fortified milk—and your body makes vitamin D from the sun.

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