At a time like this, there is a tunnel-vision focus on our immune health. This amazing yet complicated barrier against the pathogens, disease and illness that surrounds us. If you’d like some more information on the immune system please click here.
Good nutrition is the utmost form of self-care. The best thing that you can do to support your immune system is by enriching your diet with nutrients clinically proven to help the inner workings of the immune system.
Nutrients that have EFSA approved health claims for immune support
The European food safety authority (EFSA) studies these individual nutrients and there claims to either authorise or unauthorise the use of such claims in marketing and scientific articles. All of the following nutrients have the approved claim that they ‘ contribute to the normal function of the immune system’
● Vitamin B9/ Folate
● Vitamin A
● Vitamin B12
● Vitamin C
● Vitamin D
More on these nutrients...
Copper is a trace element within our body. This means that minimal amounts are needed by the adult body, approximately 1.2mg/day for an adult. It has numerous roles but also plays a part in immune health. Studies have shown that copper deficiency can lead to a decreased efficiency and effectivity of the cell-mediated and humoral immune responses, as well as the number of white blood cells called neutrophils.
Copper is found in small amounts in a number of foods including:
● Seafood (mussels, oysters and clams)
● Mushrooms (shitake and portobello)
● Root vegetables (sweet potato, turnip greens and potatoes)
● Legumes and beans (chickpeas, lentil and kidney beans)
Moreover, you can try a copper supplement. Typically these come in the form of copper gluconate, copper picolinate or copper sulphate. Copper is often combined with Zinc for powerful immune support.
You could naturally boost your intake of copper by simply taking a supplement or adding natural food sources to your meal. For example adding spinach to soups and stews, incorporating seafood or switching meat for tofu once a week.
Vitamin B9/ Folate
You may see Vitamin B9 written as folate or folic acid. Folate is the natural form and folic acid the synthetic form. For now I will refer to it is as Vitamin B9. The daily adult requirement for vitamin B9 is 200mcg/0.2mg. Research has found that vitamin B9 is required for DNA synthesis involved in cell proliferation and differentiation during the immune response. Some studies even suggest a decrease in the effectivity of the cell-mediated immune system. Most noticeably there is a decrease in CD8+ T cells and natural killer (NK) cells.
Here is a list of foods rich in Folate, the natural source of Vitamin B9:
● Yeast extract or marmite
● Soy products (beans, tofu or milk)
● Legumes and beans (lentils, chickpeas and pinto beans)
● Vegetables (spinach, kale, collard greens, asparagus and broccoli)
Alternatively, you can receive vitamin B9 as part of a supplement. This is typically in the form of folic acid or 5-methyltetrahydrofolate. I’d recommend this as a solo-ingredient formula or as part of a vitamin B complex.
You can increase your vitamin B9 intake by taking a daily supplement or increasing food sources of folate. Try a mixed greens salad with kale and spinach. Bulk out meals with legumes and beans or switch you usual dairy for a soy milk alternative at breakfast.
Selenium is another trace element found in small amounts within the body. The adult daily requirements for selenium are between 60-75mcg for men and women. Dietary selenium is used to make selenoproteins. Overall, there are 25 and some of them are used to support immunity. Those required for immune function include glutathione peroxidases (GPXs), Thioredoxin reductases (TXNRDs), Iodothyronine deiodinases (DIOs) and methionine-R-sulfoxide reductase B1 (MSRB1).
Below is a list of foods rich in selenium:
● Brazil nuts
● Seeds (chia, flax, and sunflower)
● Shellfish (oysters, clams and lobster)
● Meat (chicken, steak and pork)
● Complex carbohydrates (brown rice and wholewheat pasta)
You can also increase dietary selenium by taking a selenium supplement. Typically this comes in the form of sodium selenite. I would recommend taking selenium alongside iodine for the best effects.
As is previously mentioned above you can take a singular selenium supplement each day or increase the source of selenium in your diet. For example, you could replace your usual snack with a couple of brazil nuts or sprinkle seeds on porridge or salads.
Vitamin A can be in the form of retinol or carotenoids. Retinols are found in animal products and carotenoids can be found in plant-based sources. The daily adult requirement for Vitamin A is 600-700mcg for men and women. Vitamin A plays a role in both the humoral and cell-mediated immune responses. Moreover, the primary barrier and defence mechanisms against pathogens invading the body is the skin, epithelium and mucosa, all of which Vitamin A is critical for developing.
Foods rich in Vitamin A include the following:
● Sweet potatoes
● Butternut squash
● Fish and seafood (tuna, mackerel and clams)
Vitamin A can also be sourced from a number of natural or synthetic supplements. You can gain Vitamin A from whole foods such as spirulina and chlorella, as well as beta-carotene. Or you can get tablets that contain retinol too.
Vitamin A can be taken in dietary supplement form or increased via your meals. You could try increasing the volume of orange and red vegetables on your plate. Or try to incorporate fish 1-2 times a week.
Vitamin B12 is known a cobalamin, it can come in many different forms such as cyano-, methyl-, hydroxycobalamin etc. The daily adult requirements for this is 1.5mcg/day. Vitamin B12 is thought to be associated with important immune cells such as the natural killer (NK) cells, CD4 and CD8 lymphocytes.
Here are some foods that are rich sources of Vitamin B12:
● Seafood (clams, mussels, oysters and scallops)
● Fish (trout, mackerel, salmon and tuna)
● Meat (beef and lamb)
● Fortified cereals
● Fortified tofu
Many vegans and vegetarians are recommended to take a daily Vitamin B12 supplement as there are few natural foods (unfortified) that are rich in Vitamin B12. Typically a Vitamin B12 supplement can be found in cyano- or methylcobalamin forms. I’d recommend using this as part of a vitamin B complex tablet.
To increase Vitamin B12 in the diet you can take a daily supplement or use nutritious sources from your food. Always read the label of cereals, tofu, milk alternatives to ensure they have been fortified with Vitamin B12. Moreover, increase vitamin B12 food sources such as fish, meat and seafood in your daily meals.
Vitamin C is also known as ascorbic acid. It is a powerful antioxidant used in the body to support the immune system. Every day we are recommended to consume 40mg of vitamin C. According to research, Vitamin C plays an important role internally in the immune cells. For example, it is thought to accumulate in phagocytic cells (phagocytes, a type of white blood cell). In these cells, it helps with a process called chemotaxis. Chemotaxis is defined as ‘the unidirectional movement of a cell in response to a chemical gradient in the direction from a low to a high concentration of chemoattractant. The directed migration, or chemotaxis, of immune cells is an essential feature of the immune system.’ Anecdotally, we know that sailors who suffered from the Vitamin C deficiency state called scurvy were more susceptible to infections, suggesting that their immune system was suppressed.
Foods rich in Vitamin C include:
● Fruit (guava, kiwi, strawberries, citrus fruit, melon and tomatoes)
● Vegetables (broccoli, peppers, kale and spinach)
Vitamin C can also be obtained in supplemental form. Of course, this can be through a powdered fruit/vegetable source of the wholefood. It can also be provided in its synthetic form of ascorbic acid or as a mineral ascorbate (calcium ascorbate and sodium ascorbate). I’d recommend pairing this with Iron. It’s easy to increase your vitamin C intake, simply eat more fruits and vegetables. Don’t forget that we recommend 5 or more servings of fruits and vegetables a day.
Currently, Vitamin D is being heavily researched. As a result, we are now aware of the ramifications of Vitamin D for immune health. Vitamin D is known as cholecalciferol for vitamin D3 and ergocalciferol for vitamin D2. Our daily requirements for Vitamin D is 10mcg. Vitamin D can be created in the body through a combination of the suns rays and an inactive form in our skin. However, in the northern hemisphere and in winter, we do not often get enough sun. This is why there are food sources too. Studies have shown that people deficient in Vitamin D have higher self-reported incidences of upper respiratory tract infections. The same trend has been found in reports of bacterial vaginosis, influenza and HIV. Alternatively, one study found a 42% decrease in the incidence of influenza after a therapeutic dose of Vitamin D was given.
Here are a few rich food sources of Vitamin D:
● Fish (salmon, swordfish, rainbow trout and sardines)
● Fortified products (milk, margarine, tofu and milk alternatives)
Vitamin D can also be sourced in supplement form. This is one of the most popular supplements on the market. You can get the D3 form from lanolin, or sheep’s wool. Whereas the vegan form (D2) is extracted from lichens or mushrooms. I’d recommend taking your Vitamin D supplements alongside Vitamin K and Calcium.
You may like to increase your Vitamin D with a supplement or you can do this by improving dietary intake or lifestyle factors. Try increasing your intake of fish to twice a week. Try eggs for breakfast instead of your usual toast or cereal. Improve your label reading skills and look out for fortified products. Moreover, when the sun is shining take 15 minutes with unprotected skin to absorb the necessary vitamin D. Following this 15 minutes cover up and take the right precautions to protect your skin.
Zinc is the ‘Z’ in the A-Z of vitamins and minerals. This means it’s often forgotten about. That being said it has fantastic beneficial qualities to your health, and not only to the immune system. Our daily requirements for zinc are 9.5mg for males and 7mg for females. The role of zinc in the immune system is for non-specific immunity, upon the first infection of a particular pathogen. In particular, zinc aids the production and development of neutrophils and natural killer (NK) cells. In addition to its immune support claim, Zinc also carries an EFSA approved health claim for the following ‘contributes to normal DNA synthesis’, this means it is involved in replication and differentiation of important immunological cells.
Listed below are some foods that contain zinc:
● Seafood (clams, lobster and oysters)
● Nuts and seeds (hemp seeds, pine nuts, pumpkin seeds and cashews)
● Legumes and beans (black beans, black-eyed peas and lentils.
Zinc can also be used in supplemental form. This typically is sourced from zinc picolinate, zinc citrate, zinc sulfate and zinc gluconate. I would recommend taking this alongside selenium for powerful immune support.
Zinc can easily be increased in the diet by including a range of protein sources. For example, having some vegetarian meals including beans and tofu, then including a meal with beef, and then seafood.
Remember that the immune system is made up of many, many cells. Each one needs your support. So, nourish your body and it will protect you as best it can.
WRITTEN BY HARRIET HUNTER, ANUTR. NUTRITIONIST