Having a healthy immune system is important as it prevents us from getting sick. Lifestyle factors such as adequate sleep, maintaining a healthy weight range and regular physical activity help provide the right foundations for our immune system to function at its best. It can also be considerably affected by the foods we eat.

Over 70% of our immune system resides in our gut so what we eat forms the foundation of our health. There is some evidence to show improving nutrition helps to support optimal immune function. Whilst research is continuing to explore the effect of diet on the immune response, eating a healthy and balanced diet is a good way to start.

Your immune system maintains homeostasis (the body’s way of regulating our internal environment) by defending against viruses and bacteria which can cause inflammation in the body, illness and disease. There is some evidence that various nutritional deficiencies can impair immune function increasing both the risk and severity of the infection.

Eating a wide variety of nutrient dense foods daily is the best step to optimise the function of our immune system. Research shows nutrients like vitamin C, zinc and selenium support immunity. Here is a list of evidence based immune boosters and natural food sources to help supercharge your diet.


Good Sources


Meat, chicken and fish. Vegetarian sources include legumes and whole grains


Nuts (particularly brazil nuts), meat, cereals, mushrooms


Seafood (particularly oysters), meat, chicken, dried beans and nuts

Vitamin C

Oranges, lemons, limes, berries, kiwifruit, broccoli, tomatoes and capsicum

Vitamin E

Nuts and green leafy vegetables


Cereals, legumes, green leafy vegetables, fruits, nuts, fish, chicken and meat

B9 (folate)

Green leafy vegetables, legumes, nuts and seeds, commercial bread-making flour

B12 (cyanocobalamin)

Animal products, including eggs, meat and dairy and in some fortified soy milk (check the nutrition information panels)

Vitamin D

Sun exposure through a few minutes outdoors most days, eggs, fish and vitamin D fortified foods like some milk brands.

Vitamin A

Oily fish, egg yolks, cheese, tofu, nuts, seeds, whole grains and legumes

There are many health benefits associated with balanced vegetarian eating patterns.  Recent research efforts have highlighted the potential of this way of eating to strengthen our immunity. Whilst the exact reason for this is still being investigated, one theory pointing to any associated health benefits is the higher consumption of plant-based foods including fruits, vegetables and legumes which contain beneficial compounds like antioxidants, phytosterols and vitamins and minerals.

Sometimes our immune system fails, but overall, it does a tremendous job of protecting us against illness and disease. Eating a healthful, balanced diet supported by mindful lifestyle choices can naturally help to keep our immune system strong and healthy.

Obtaining immune boosting nutrients from food is preferred, but supplements may be of benefit if your dietary intake is inadequate. Be sure to speak with your healthcare professional or dietitian for the best advice and a tailored approach for your individual health needs, before taking any supplements.


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