Best Vitamins for Immune Systems and the Foods That Have Them
With the coronavirus disease 2019 (COVID-19) continuing to spread and cold and flu season just around the corner, more people are stocking up on vitamins and eating foods that boost their immune systems.
Vitamins and certain minerals are essential to the body, and without these nutrients, the body cannot function properly. Foods and supplements packed with vitamins help the body work properly.
Although many vitamins have different purposes, some vitamins are specifically geared toward helping the body’s defense system fend off infections and other toxins. Some of the best vitamins and foods containing the vitamins, that provide immune support include:
Vitamin A is considered an anti-infection vitamin because it helps in producing white blood cells (lymphocytes) in the immune system that fight bacteria, viruses, and other toxins that can cause disease.
Vitamin A is found naturally in a variety of foods that include:
- Oily fish, such as salmon and mackerel
- Dairy products, including skim milk
- Green leafy vegetables, such as broccoli and spinach
- Orange and yellow vegetables, such as carrots and squash
- Fruits, such as apricots, mangos, and cantaloupe
Fortified breakfast cereals also contain Vitamin A. Fortified means adding a vitamin or mineral to the food.
B vitamins are called the “building blocks of the body” because the nutrients help form red blood cells, help the immune system in its fight against bacteria and viruses, and help the body keep up its energy level. The B complex includes:
- B1 (thiamine)
- B2 (riboflavin)
- B3 (niacin)
- B5 (pantothenic acid)
- B7 (biotin)
- B9 (folic acid)
Vitamin B can be found in foods rich with protein, such as fish, meat, poultry, eggs, dairy, leafy green vegetables, beans, peas, and some breads and cereals.
Vitamin C has a reputation as a “fighter” vitamin because its antioxidant properties help to protect the body’s cells against free radicals. It’s also the vitamin many people reach for at the first sign of a cold.
Studies have found that a high intake of vitamin C reduces the risk of cardiovascular disease, cancer, and other chronic diseases, said Tamar Samuels, a registered dietitian, a national board-certified health and wellness coach, and co-founder of Culina Health.
The body does not make vitamin C so the nutrient must come from supplements and foods, like fruits and vegetables. Fruits that are good sources of vitamin C include:
- Berries (strawberries, raspberries, blueberries, cranberries)
- Citrus fruits and juices, such as orange and grapefruit
Vegetables with the highest amounts of Vitamin C include:
- Broccoli, Brussels sprout, and cauliflower
- Green and red bell peppers
- Sweet and white potatoes
- Green leafy vegetables (spinach, cabbage, turnip greens)
- Tomatoes and tomato juice
While vitamin D is important in maintaining strong bones, studies suggest the nutrient may be helpful in treating and preventing autoimmune disorders, such as multiple sclerosis, lupus, and Type 1 diabetes.
In recent months, vitamin D has been the focus of COVID-19 studies that explore whether a vitamin D deficiency increases the risk for the coronavirus. However, the National Institutes of Health (NIH) and the World Health Organization say there is not enough data to recommend using vitamin D to prevent or treat COVID-19.
While the body can produce vitamin D through exposure to the sun, foods such as oatmeal, mushrooms, salmon, egg yolks, some cereals (like Raisin Bran), orange juice, cow’s milk, and soy milk, are fortified with vitamin D.
Vitamin E is an all-around powerhouse of a vitamin. According to the NIH, the body needs vitamin E to help the immune system stand strong against viruses and bacteria. The vitamin also protects body tissue against free radicals which can damage cells, tissues, and organs.
Vitamin E is found in such foods as:
- Butternut squash
- Green leafy vegetables (such as broccoli and spinach)
- Sunflower seeds
Nuts and seeds, like sunflower seeds, almonds, hazelnuts, and peanuts, are also good sources of vitamin E.
Minerals Also Help The Immune System
Minerals work alongside vitamins to support the immune system. For instance, studies show that the mineral selenium helps in reducing oxidative stress, which is an imbalance between free radicals and antioxidants. This imbalance can lead to cell and tissue damage. Foods such as broccoli, garlic, tuna, sardines, and brazil nuts are good sources of selenium.
Another familiar mineral that plays a key role in boosting the immune system is zinc. Although there is conflicting research on zinc, the mineral is thought to reduce the duration and severity of cold symptoms by preventing viruses from entering cells and stopping them from multiplying in the body, said Samuels. In addition, Samuels said zinc must be consumed through foods because the body cannot store the mineral.
While zinc is found in a wide variety of foods, the NIH says oysters contain more zinc per serving than any other food, followed by red meat and poultry. Other sources of zinc include beans, nuts, whole grains, fortified cereals, dairy products, and certain types of seafood, such as crab and lobster.
Immune System Gets Boost With Prebiotics and Probiotics
Besides vitamin and minerals, prebiotics and probiotics have been shown to boost the immune system by discouraging the growth of harmful bacteria in the gut (gastrointestinal system).
Prebiotics are high-fiber foods that feed and encourage good bacteria to grow in the gut. Some healthy prebiotic foods include garlic, onions, leeks, asparagus, barley, almonds, chickpeas, and oats.
Probiotics are live strains of bacteria that add to the population of healthy bacteria in the digestive system. Most fermented foods naturally contain probiotics or have probiotics added to them. The most familiar probiotic food is yogurt, but pickles, sauerkraut, sourdough bread, and drinks such as tempeh and kombucha also contain probiotics.