Your Gut and Immunity

With the outbreak of COVID-19, there is a growing importance to boost one’s immunity. Our immune system helps to identify and attack a variety of threats such as viruses, bacteria and parasites; and is affected by age as well as medical conditions such as diabetes and obesity. Did you know that your gut contains 70% of the cells of the immune system? There is a complex relationship between the gut bacteria and one’s immunity, which is why a healthy gut will provide nourishment to a healthy immune system.

The intestine’s impact on health


As we can see, the intestines not only are for digestion of foods but it also affects one’s overall health as well as immunity. This is probably also due to the intestinal microbiome and how it helps to prevent infections and pathogens from crossing the gastrointestinal barrier. Hence the talk of consuming probiotics or ‘good’ bacteria, which will help to reduce harmful bacteria.

Taking care of your diet

In order to boost your immunity overall, it is important to reduce your intake of processed foods and sugars, while increasing the amount of fruit and vegetables. This is because important micronutrients and antioxidants such as zinc, selenium, iron, copper, folic acid, vitamins C, B6, E and A are able to help maintain gut health. Moreover, some doctors do recommend intermittent fasting as this promotes autophagy – a process where the body naturally digests and removes dead cells.

Heard of the advice to eat a ‘colourful plate’? This is because the various colours of fruit and vegetables are an indication of the types of antioxidants or phytochemicals they contain. As such, eating a colourful plate means that you’re consuming a variety of micronutrients that can help boost your immunity.

Colour code system of fruit and vegetables

Colour Phytochemical Fruit and Vegetables
Red Lycopene Tomatoes and tomato products, pink grapefruit, watermelon
Red/purple Anthocyanins, polyphenols Berries, grapes, red wine, prunes
Orange α-, β-carotene Carrots, mangoes, pumpkin>/td>
Orange/yellow β-cryptoxanthin, flavonoids Cantaloupe, peaches, oranges, papaya, nectarines
Yellow/green Lutein, zeaxanthin pinach, avocado, honeydew, collard and turnip greens
Green Sulphoraphanes, indoles Cabbage, broccoli, Brussels sprouts, cauliflower
White/green Allyl sulphides Leeks, onion, garlic, chives

Another important vitamin is Vitamin D which is naturally produced by the body when directly exposed to sunlight and it regulates absorption of calcium and phosphorus, as well as an important pro-survival molecule in the immune system. Besides getting some daylight, you can also get vitamin D from foods such as salmon, sardines, egg yolks, prawns, milk and yoghurt.

Prebiotics are also important ‘food’ for your probiotics, which is why fibre from vegetables and whole grains are helpful to maintaining a healthy gut.  Fermented foods such as kimchi and kombucha are also anti-inflammatory and can help boost the health of the microbiome. Don’t forget to drink sufficient water too!

While eating probiotics is good, do consume a diverse amount of probiotics which is more important than the count as different probiotics help different health conditions. For example, lactobacillus acidophilus helps with overall digestion, nutrient absorption and vaginal health in women while lactobacillus paracasei helps with liver health.

Having a healthy lifestyle

Besides eating well, other aspects of your lifestyle will also affect your immune system. We all know that it is important to have adequate sleep, reduce or give up smoking, have proper stress management and exercise regularly. Exercising improves one’s blood circulation and also immune cell function.


We will be having a Basic Kombucha Workshop on Sat, 21 March 2020. If you’d like to learn how to make this fermented tea that will diversify your probiotic intake, do check out the details below:


Dr Melvin Look, Consultant Gastrointestinal and Laparoscopic Surgeon, PanAsia Surgery
Bischoff BMC Medicine 2011, 9:24,

Images: PanAsia Surgery, Pixabay and Unsplash

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