At a time when we scientists are still trying to understand the basics of how the immune system works, product manufacturers have rushed to market everything from cereals to herbal teas that purport to support immunity with little evidence to back up those claims. Keep this in mind when you are tempted to pay extra for one of these products: consuming a food or supplement that contains vitamins, antioxidants, or other substances intended to support immunity delivers no additional benefit beyond that of taking an ordinary multivitamin pill.

Read more: The Truth About Your Immune System – Harvard Health Publications.