Support your immune system through your diet

boost immune health - thrive magazine

From the moment of birth, our bodies are bombarded by different pathogens and to combat them we need our immune system to target the pathogens, and handle any damage caused by other factors, like external pollutants or toxins in food. Not surprisingly, nutrients present in our diet play an enormous role in maintaining the function and health of the immune system.

Nutrients required for immune system health:
Every stage of immune response is heavily dependent on the presence of specific micronutrients, including essential amino acids, essential fatty acids, vitamins and minerals. Those nutrients play vital roles in maintaining quality immune system functions; thus, all forms of immunity may be affected by their deficiencies. When your immune system is challenged, it’s demand for nutrients suddenly increases, therefore you should take care to ensure that your diet provides this demand for nutrients.

Some of the essential nutrients and vitamins need for gut health

1 – Protein and amino acids
Amino acids are required for the synthesis of a variety of specific proteins, which regulate key metabolic pathways of the immunity and so, deficiency of either protein or amino acids can negatively impact on the immune function and increase your susceptibility to infections. Great sources of protein are; meats, fish, beans and bean-made flours, diary and eggs.

2 – Fatty acids
Dietary fatty acids are very important for immune health. Both Omega 6 and Omega 3, are important to maintain cell membranes. In Western society, our diet tends to be rich in omega 6, rather than omega-3. A balance of Omega-3 and Omega 6 is very important for gut health and omega 3 can be found in flaxseeds, chia seeds, fatty fish, such as salmon, herring or tuna.

3 – Prebiotics and probiotics
Gut bacteria plays an important role in protecting us against pathogens. By colonising your intestines, they not only protect our digestive system from infections, but also, they stimulate and maintain immune system defences.

– Probiotics help you to increase the number of friendly bacteria in your gut. Most of them are rich in bacteria cultures, especially lactobacilli and bifidobacterial, which you can find in traditionally cultured dairy products, like mature cheeses, some fermented milks, live yogurt and kefir, as well as in sauerkraut/kimchi, miso/natto paste or soya/fish sauce.

– Prebiotics are non-digestible carbohydrates, known as dietary fibres. Those fibres are an important energy source for gut microbes and are used to produce short-chain fatty acids, which reduce allergic inflammation, improve the gut barrier by increasing mucus production, and reduce risk for colorectal cancer and Crohn’s disease. Therefore, dietary fibre plays an important role in gut health and we should try to include more fibre into our diet – at least 25–31 g per day. You can find fibre in whole foods, such as cereals, vegetables, fruits and nuts, as well as in Flaxseed, Almonds, Wheatbran, Barley, rye, Oats, beans, Soy, Spinach, Lentils.

4 – Vitamin C
Vitamin C is necessary for collagen production and antioxidant defences, top up your vitamin C levels with acerola cherries, guavas, yellow and red peppers, mustard spinach, kiwifruit, litchis, oranges, pumelo, lemons, chilli peppers.

5 – Vitamin D
This stimulates production of antimicrobial peptides in the respiratory tract and protects your lungs from infection. It can be found in fish, such as carp, mackerel, salmon, halibut, trout, but also exposure to UV light enables our body to make Vitamin D.

6 – Vitamin A

This regulates your immune cells and modulates microbiota in the gut. It can be found in sweet potatoes, carrots, pumpkin, beef liver, tuna, spinach, mustard greens, butternut squash, collards, cantaloupe melon.

7 – Vitamin E

This decreases inflammation and protects cells against oxidative damage from free radicals. It can be found in sunflower seeds, almonds, fortified plant-based drinks, avocados, hazelnut/almond oil, nut butter.

8 – Vitamin B
Vit B complex improves immune response during disease, protects your cell DNA against damage and boosts cell response to pathogens. Best sources are fish, poultry, beans, lentils, sweet potatoes, bananas, avocados, pistachios, edamame.

9 – Zinc
Zinc enhances bacteria elimination in your digestive tract and modulates antioxidant defences, it can be found in seafood, beef, chicken, tofu, natto, pork chop, hemp or pumpkin seeds.

10 – Copper
Copper has shown to have antimicrobial properties and efficiently destroys ingested pathogens. It can be found in seafood, shiitake and white button mushrooms, tofu, soyabens, sweet potatoes, sesame seeds, sunflower seeds, hemp seeds.

11 – Selenium
This regulates redox reactions in your body and protects against oxidative stress, by removing free radicals from your body. It can be found in brazil nuts, fish/seafood, pork chops, beef, poultry, tofu, whole grains.

12 – Magnesium
This maintains antioxidant defences, reduces oxidative stress. It can be found in spinach, swiss chard, hemp seeds, pumpkin seeds, flaxseeds, beans, tuna, quinoa.

So, as you can see immune health is a complicated topic and involves a myriad of nutrients from our diet and systems within our body. To maintain immune health, it’s always a good place to start to look at eating a balanced diet, rich in fibre, vitamins and the above nutrients. If you do feel that you need to boost your levels of bacteria in the gut – always see a registered nutritionist or Dietitian to discuss your symptoms first.

Food list are from My Food Data database. Available here:
Recommended Daily Allowances of vitamin and minerals. Institute of Medicine. Dietary Reference Intakes for Calcium and Vitamin D. The National Academies Press; Washington, DC, USA: 2011.
Cadler PC. Feeding the Immune System. The Proceedings of the Nutrition Society. 2013; 72(3): 299-309.
Calder PC, Kew S. The immune system: a target for functional foods? Br J Nutr. 2002 Nov;88 Suppl 2:S165-77.
Devinder D, Mona M, Hradesh R, Patil RT. Dietary Fibre in foods: a review. J Food Sci Technol (May–June 2012) 49(3):255–266.
Gombart AF, Pierre A, Maggini S. A Review of Micronutrients and the Immune System–Working in Harmony to Reduce the Risk of Infection. Nutrients. 2020 Jan; 12(1): 236.
Maggini S, Pierre A, Calder PC. Immune Function and Micronutrient Requirements Change over the Life Course. Nutrients. 2018 Oct; 10(10): 1531.
Li P, Yin YL, Li D, Kim SW, Wu G. Amino acids and immune function. Br J Nutr. 2007 Aug;98(2):237-52. Epub 2007 Apr 3.
Tam M, Gómez S, González-Gross M, Marcos A. Possible roles of magnesium on the immune system. Eur J Clin Nutr. 2003 Oct;57(10):1193-7.
Venter C, Eyerich S, Sarin T, Klatt KC. Nutrition and the Immune System: A Complicated Tango. Nutrients. 2020 Mar 19;12(3).

(Cadler and Kew, 2002; Gombart et al., 2020).

Written by Nutritionist Joanna Jurek, Joanna has a BSc in Biomedical Science and is completing a PhD in Human Nutrition.