The human immune system is made up of tissues, blood cells and organs that come together to protect the body from germs and infections, as well as life-threatening diseases. A well-balanced diet, consisting of all of the essential vitamins and nutrients, combined with normal physical activity, will help keep this system working at its best. All vitamins that are required for normal growth and function will play a role in maintaining immune system strength; however, a few vitamins and minerals are essential to improving the immune system.
Vitamin E
Vitamin E is made up of a family of eight different antioxidants, consisting of four tocopherols and four tocotrienols. Of the eight, alpha-tocopherol, a fat-soluble vitamin that inhibits oxidation of the body's cells by free radicals, is most useful to the human body. Damaged cells could potentially lead to cancer or various forms of heart disease, states the National Institutes of Health. The Recommended Daily Allowance (RDA) for vitamin E for healthy individuals over the age of 14 is 15 mg. Good food sources of vitamin E include peanut butter, safflower oil, almonds, tomatoes and spinach.
Vitamin C
Like alpha-tocopherol, vitamin C is an antioxidant that protects the body from free radicals. According to the Linus Pauling Institute, vitamin C has the ability to reproduce vitamin E, as well as influence the production of white blood cells, both of which can help to protect cells from oxidation. Being a water-soluble vitamin and secreted through urine, vitamin C must be replenished through a healthy diet. The RDA for vitamin C for the average adult female is 75 mg and 90 mg for adult males. Various fruits and vegetables supply this vitamin, such as oranges, strawberries, tomatoes, potatoes and broccoli.
Iron
Iron is essential for the transportation of oxygen to the cells. A majority of the iron in the human body is in the proteins of the red blood cells, hemoglobin, whose primary job is to carry oxygen from the lungs to tissues throughout the body. Adequate iron levels will keep the body strong and functioning normally. When you are iron-deficient, you may become weak, fatigued and possibly anemic. In this state, it is extremely hard for your body to fight off disease or illness. The RDA for iron is 8 mg for men and 18 mg for women. A wide range of foods supply iron, including seafood, beef, spinach and beans.
