Eating a diet rich in certain vitamins and minerals just might reduce the number of colds and flus you catch as well as lower your risk for more serious illnesses. Many vegetables, fruits, nuts and fish provide these potentially immune-supporting nutrients. No single nutrient can cure or prevent illness, though. Instead, a variety of nutrients work together to strengthen your body's ability to fight off illness.
Vitamins
Among the vitamins that may support the immune system are vitamins C, E, D, A, B6 and folate. Vitamins C and E are both antioxidants that help protect cells from damaging free radicals. Vitamin D is essential for the function of immune system cells such as T-cells and the cells that produce antigens. Low blood levels of vitamin B6, or pyridoxine, may weaken the immune system, especially in older adults.
Minerals
Immune-supporting minerals include zinc, selenium, iron and copper, note experts from Harvard University. Zinc and selenium are necessary for proper immune function, and both also work like antioxidants. The body uses iron to produce T-cells and reactive oxygen species -- chemicals that kill pathogens. Copper also helps maintain the immune system, and deficiency in this mineral can weaken immunity, particularly in infants.
Dosages
For your immune system to function properly, your body must get enough of each required nutrient. You need at least 75 mg of vitamin C daily if you're a woman and 90 mg if you're man, according to medical experts at the University of Maryland. Women should get 8 mg of zinc daily, whereas men need 11 mg. Teens and adults of both genders need 15 mg of vitamin E, 50 mcg of vitamin D and 55 mcg of selenium daily.
Sources
A varied, balanced diet is more effective than supplements. You can get significant amounts of vitamin C from citrus fruits and broccoli, vitamin E from nuts and vegetable oils such as olive oil, vitamin D from salmon, mackerel and fortified foods, and vitamin B6 from salmon and bananas. For zinc, eat oysters and red meats, and for selenium, try Brazil nuts, fish or brewer's yeast. Many other foods contain these nutrients, so research to find the sources you prefer. If you have a serious health condition or use medications, consult your health care provider before taking dietary supplements.
Additional Nutrients
Vitamins and minerals aren't the only nutrients that may help strengthen your immune system. The carotenoids, bioflavenoids and omega-3 fatty acids in foods may also boost your immunity. Get carotenoids from orange or yellow vegetables and fruits such as carrots, yams, winter squash and apricots. For omega-3s, eat nuts and oily fish such as salmon and mackerel. Fruits and vegetables in general are sources of bioflavenoids.
