The Best Foods to Eat to Boost Immune System
Over the past several decades, there has been emerging interest in the study of the human immune system. Experts have discovered the many repercussions of a weakened immune system response. A body with a weak immune response has a more difficult time combating viral infections (e.g., coronavirus/COVID-19), pathogens, and other foreign substances.
Dietary and lifestyle habits are known to affect immune health, altering both its innate and adaptive functions. A daily diet consisting of necessary nutrients is essential for building and supporting a healthier immune system. They may also boost immune system responses. The immune system’s cells include many different types of white blood cells. They are essential for defending the body against viruses and pathogens.
This article will examine the role vitamins and minerals play in immune system health. It will also identify the foods with the highest concentrations of these important micro-nutrients.
Vitamins and Minerals that Boost Immune System Responses
Vitamin A (also known as the “anti-inflammatory vitamin”) is a group of unsaturated, nutritional, organic compounds that includes retinol, retinal, and retinoic acid, among others. They play a crucial role in the diverse physiological processes of the human body, including the development of the immune system and regulation of cellular and humoral immune responses (i.e., an antibody-mediated response).
Vitamin A is also involved in different immunity-related aspects like regeneration of mucosal barriers and strengthening the activity of the white blood cells such as neutrophils, macrophages, lymphocytes, and NK (Natural Killer) cells.
Vitamin A also plays an influential role in the production of immunoglobulins (i.e., antibodies), and supports many antioxidant processes.
Foods high in vitamin A include beef liver, lamb liver, liver sausage, cod liver oil, sweet potato, winter squash, kale, collards, turnip greens, carrot, mango, cantaloupe, pink or red grapefruit, and watermelon. Because vitamin A is fat-soluble, it is best to consume the vegetables and fruit that contain vitamin A with healthy fat (e.g., olive oil, avocado, etc.).
Vitamin E is a fat-soluble antioxidant that is needed in immune system cells. Its importance to the immune system has been long studied; thus, it is considered one of the most effective natural elements known to influence immune function.
This fat-soluble vitamin has anti-inflammatory properties and may help with the growth and activity of white blood cells like macrophages, NK cells, lymphocytes, and dendritic cells. Vitamin E also helps with the promotion of T-cell maturity and plays an essential role in the enhancement of immunoglobulin (i.e., antibodies) levels, antibody responses, interleukin production, and signal transduction between white blood cells.
Vitamin E is essential for immune system health because it defends cell membranes against oxidative damage. By reducing oxidative damage, vitamin E may indirectly help enhance the activity of the immune system cells.
As we age, cell membranes become more prone to oxidative damage, and our immune system’s cells’ ability to protect our body weakens, potentially exposing us to more diseases. Therefore, it becomes even more important to supply our body with healthy foods that support immune system health.
One example of a vitamin E-rich, healthy food is the almond. Almonds are rich in vitamin E and researchers at the Institute of Food Research in Norwich, England, and the Policlinico Universitario in Messina, Italy found that the skin of almonds contains compounds that strengthen white blood cells in a way that allows them to find and destroy viruses. They are also a source of iron and protein, which are essential for the health of the immune system. Almonds contain omega-3 essential fatty acids, magnesium, niacin, riboflavin, and potassium.
Other foods high in vitamin E include wheat germ oil, sunflower seeds, peanuts, hazelnut oil, avocados, spinach, swiss chard, pine nuts, and butternut squash.
Also known as L-ascorbic acid, this essential micronutrient must be included in daily nutrition because the human body is unable to make it on its own. Vitamin C is essential for numerous biochemical and physiological processes in the body. It plays a vital role in the immune system response.
Some of its vital functions include:
- regulation of enzymatic and antioxidant processes
- enhancement of white blood cell chemotaxis (i.e., directed movement of a cell)
- phagocytosis (i.e., when a cell engulfs a bacteria or particle)
- microbial killing
Vitamin C is important for the rapid growth of specialized immune cells (e.g., B and T cells) and can help reduce tissue damage and necrosis (i.e., premature cell death).
One example of a vitamin C-rich food is the Amla berry or Indian gooseberry. It is the central ingredient in the centuries-old Ayurvedic immunity booster, chyawanprash. Both the fresh and dried berries contain an extremely high level of vitamin C that is more than most other fruit. It has a slightly bitter taste and is best consumed as a juice or jam. It is also available in a supplement/dried powder form.
Other foods high in vitamin C include Barbados ‘acerola’ cherry, Kakadu plums, rose hips, chili peppers, guavas, sweet yellow peppers, Camu Camu, blackcurrants, thyme, parsley, mustard spinach, kale, kiwis, broccoli, Brussels sprouts, lemons, lychees, American Persimmons, papayas, strawberries, and oranges.
Zinc is an essential mineral for the immune system response. It uses specific mechanisms to strengthen immunity, including assisting with the production and activity of white blood cells like neutrophils, lymphocytes, macrophages, and NK cells.
Zinc is also needed for phagocytosis, intracellular killing, and immunoglobulins (i.e., antibodies), interleukins, and cytokines production.
It is known for reducing the symptoms of multiple infections, including the common flu, recurrent ear infections, and upper and lower respiratory tract infections, among others. Researchers are studying its effects on COVID-19, also known as the coronavirus.
Some foods high in zinc include meat, shellfish, oysters, legumes (e.g., chickpeas, lentils, and beans), seeds, nuts, dairy, eggs, and whole grains.
Vitamin B12 is a water-soluble vitamin that helps the body’s metabolism by turning food into energy. It plays an essential role in the growth of red blood cells and the preservation of normal DNA, both of which are necessary for maintaining the body’s optimal function.
Vitamin B12 helps create white blood cells, like the B-cells, and the growth of T-cells. The immune system needs B12; a deficiency can reduce the immune response.
One study noted that participants with a B12 deficiency also had suppressed NK cell activity and a “significant” reduction of T lymphocytes (T-lymphocytes are referred to as CD8+ in the study). The researchers also acknowledged “these abnormalities could be at least partly restored by methyl-B12 treatment.”
Foods high in B12 include meat (e.g., lamb, beef, and veal livers), clams, sardines, fortified cereal, tuna, fortified nutritional yeast, trout, fortified non-dairy milk, milk and dairy products, and eggs.
Because B12 is primarily in animal products, a dietary supplement may be needed for vegans and vegetarians. Consult with a doctor.
Some individuals may have a difficult time absorbing B12 from food. Their gastrointestinal tract lacks a protein called intrinsic factor, which is needed to absorb B12 from food. Many individuals are unaware of this and will need to consult with a doctor to get tested to confirm if they lack the intrinsic factor.
Also known as pyridoxine, vitamin B6 plays several vital roles within the body, this also includes the immune system response.
A 2006 study showed that critically ill patients who supplemented with 50 or 100 milligrams of B6 saw an improvement in their immune response.
Foods high in vitamin B6 include milk, tuna (yellowfin and albacore), eggs, turkey, chicken and chicken liver, beef, carrots, fortified cereals, green peas, winter squash, bananas, chickpeas, acorn squash, and butternut squash.
Magnesium is one of the most important micronutrients the body will ever need. It plays an essential role in the immune system, including the first line of immune response defense (i.e., innate immune system) and the second line (i.e., acquired immune system). Magnesium assists antibodies and white blood cells that respond and bind to other cells.
Foods high in magnesium include pumpkin seeds, kernels, almonds, spinach, avocado, cashews, legumes, tofu, seeds, whole grains, black beans, cooked brown rice, baked potato with skin, and shredded wheat (cereal).
Selenium is a strong, nutritional antioxidant required by the body for the maintenance of several different functions. The most notable is the vital role it plays in the thyroid gland and the production of thyroid hormones. When it comes to the immune system, some studies have shown that selenium strengthens both cell-mediated and humoral immune responses.
Conversely, they have also shown that a deficiency of selenium may weaken immune responses to viruses, and pathogens, among other things. However, it is still unclear whether selenium boosts all types of immune responses.
Studies have shown that a selenium deficiency can weaken the ability of white blood cells, like neutrophils and macrophages, to kill toxins and other foreign substances, making the body potentially more susceptible to infectious viruses and diseases. Selenium contains selenoproteins that are needed in the antioxidant enzymes and the thyroid gland. The thyroid gland and antioxidant enzymes also have vital roles in the maintenance of the immune system.
Glutathione is a powerful antioxidant that can be made in the body but needs selenium for production and maintenance.
Foods high in selenium include fish, turkey, chicken, cottage cheese, eggs, brown rice, sunflower seeds, baked beans, mushrooms, oatmeal, and spinach. Also, Brazil nuts have some of the highest concentrations of selenium per nut.
Medicalnewstoday.com recommends limiting Brazil nuts to just one per day. One Brazil nut provides the complete, adult daily selenium allowance of 55mcg. Overconsumption of Brazil nuts can lead to selenium toxicity.
It is important to monitor the amount of selenium consumed. Just as with all other vitamins and minerals, too much of a good thing can be dangerous. Consult with a doctor.
Vitamins and minerals play an essential role in the body’s immune system response. They help boost immune system responses. A deficiency can comprise the immune system and its ability to fight off diseases, viral infections, and pathogens.
As we age, our immune response typically declines, so it becomes even more vital to ensure we consume sufficient levels of these vitamins and minerals. Dietary and lifestyle habits, while not always realized, can affect our bodies in more ways than one.
Vitamins and minerals cannot prevent a person from catching viruses, infections, or pathogens. However, they could help the body fight them more effectively. Vitamins and minerals provide the substances needed for the biochemical processes that occur in the immune system.
This list does not contain all the foods you need to boost your immune system. There are many more for you to choose from. Search for different options and try to include as many as you can into your daily diet. Eating right is not the only way to enhance immunity, but it is a good start to defend you and your family from several diseases.
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