Maximum Immunity: 7 Essential Nutrients

With wealth pretty much out the door for now, we would all do well to keep an extra watchful eye on our health. I know I’m going to keep this list of seven essential nutrients for immunity in my mind when I shop for my groceries. The list comes from 4 Weeks to Maximum Immunity: Disease-Proof Your Body, by the editors of Prevention Magazine.

1. Selenium: A potent antioxidant, selenium plays an essential role in immune function by protecting immune cells against free radical damage. It also helps regulate T-cells’ production of proteins called cytokines, a process that’s essential for launching a quick and vigorous immune response to an acute infection. Studies have show that selenium deficiency contributes to impaired immune function, and supplementation improves the immune system’s production of antibodies in response to foreign invaders. Top food sources: Whole grains, nuts, seeds, broccoli, and fish.

2. Vitamin A: Sometimes it’s called the anti-infective vitamin, because a deficiency of vitamin A has a strong correlation with an increased risk of infection. Researchers long have known that vitamin A is necessary to maintain healthy levels of circulating T cells. Even a modest deficiency can weaken the immune defenses of a child’s respiratory tract by damaging mucous membranes that form a naturally protective barrier against viruses and bacteria. Vitamin A also enhances the activity of white blood against viruses and bacteria. Top food sources: Dark-green leafy vegetables, bell peppers, butternut squash, cabbage, cantaloupe, carrots, and sweet potatoes. All of these contain large amounts of beta-carotene, which the body converts to vitamin A on an as-needed basis.

3. Vitamin B6: This B vitamin supports the activity of white blood cells. When researchers from Tufts School of Nutrition temporarily removed vitamin B6 from the diets of healthy older adults, immune function plummeted. Top food sources: Fish, poultry, lean meats, whole grains, leafy greens, bananas, prunes, peanuts, walnuts, and chickpeas.

4. Vitamin C: A potent antioxidant that protects immune cells from free radical damage, it’s also vital to the production of white blood cells. Although large amounts of vitamin C do not significantly lower your risk of catching a cold, supplemental doses may reduce the duration and severity of symptoms by inhibiting the release of histamine, an inflammatory chemical that causes a runny nose and respiratory congestion. Top food sources: Oranges and grapefruit, bell peppers, broccoli, cantaloupe, kiwifruit, rutabagas, strawberries, sweet potatoes, and tomatoes.

5. Vitamin D: Long known as essential for maintaining strong bones and preventing osteoporosis, it also helps the thymus gland generate a sufficient number of immune cells. Vitamin D is present in most multivitamins and calcium supplements. A few minutes of sunlight per day also can help restore your supply. Top food sources include: Eggs, butter, and fortified milk.

6. Vitamin E: This potent antioxidant sacrifices its own electrons to cell-damaging free radicals, effectively neutralizing them. Vitamin E also raises levels of interferon and interleukin, chemicals produced by the immune system to fight infection. Top food sources include: Wheat germ, molasses, whole grains, nuts, and seeds.

7. Zinc: A mineral known for its ability to lessen the severity and duration of colds, zinc plays a critical role in maintaining a strong immune system. Specifically, it helps stabilize and protect your primary barriers against infectious organisms-your skin and mucous membranes-and promotes the normal development of immune cells. Zinc also has antioxidant properties. Top food sources: Fish, shellfish, skinless poultry, and lean cuts of pork. Whole grains also contain some zinc.