Zinc functions in more enzymatic reactions than any other mineral, making it indispensable to the immune system, which is involved in reactions and signaling all the time. In particular, zinc enhances the function of helper T cells, which are important in identifying foreign antigens and alerting other cells of the immune system to invaders. Even a mild zinc deficiency can have adverse effects on the immune system, particularly in children and the elderly.
But too much zinc can be toxic and will inhibit immune function. The FDA recommends about 11 milligrams of zinc per day.
Lean meats such as beef, chicken and seafood are the best sources of zinc. Nonmeat eaters may have a harder time getting enough of the mineral because zinc in plant proteins is not as available for use in the body as zinc from animal proteins. Some options for getting zinc into a vegetarian diet include pumpkin seeds, beans and mineral-fortified cereals.
Broccoli, with its intense green color and dense florets, just looks healthy. Derived from the Latin word for "branch" or "arm," broccoli belongs to the family of cruciferous vegetables which includes cabbage, brussels sprouts, cauliflower and turnip.
"These would, for sure, be foods with extremely potent antioxidant compounds to help fight disease," Blatner said.
In the winter, when some of the more exotic fruits may be of lesser quality than the summer, broccoli and other cruciferous vegetables are an excellent -- and cheap -- source of vitamins A, C and E. In addition, broccoli is high in glucosinolates which stimulate the body's immune system.
Broccoli is a doubly powerful food because of its high concentration of sulforaphanes, which are potent anti-cancer agents.
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