Boosting our Immune System through food

How can diet boost our immune system – especially with the risk of Coronavirus?

Immune Boosting Foods

We rely on our Immune system to protect us from many illnesses – from the run of the mill coughs and colds, to influenza, stomach upsets and more serious diseases like cancer. Now we are faced with the new assault upon our health – COVID -19 Coronavirus. Its scary to think that one virus can have such a devastating effect on our lives. Is there anything we can do to help protect ourselves?

It’s clear that we should indeed follow the Government advice to prevent the virus entering our system in the first place – regular handwashing is key. This helps prevent the virus entering our body, getting rid of respiratory droplets from someone who is contagious through the most defenceless areas of our body – the eyes, nose and mouth. So, keep washing your hands and  try not to touch these vulnerable areas!

Are there Nutrients that can support our immune health?

Our Immune system controls Inflammation in the body. Although inflammation in the correct amount is the body’s way of repelling invaders and allowing healing, when it becomes excessive it has the effect of damaging cells and tissues. So, keeping inflammation under control and giving the body extra anti-oxidant nutrients to repair cell damage is our goal.

There certainly are nutrients that can boost our immune system, and the front runner is good old Vitamin C. Vitamin C fights inflammation and supports the body’s ability to fight infection. You can find it in kiwi fruits, citrus fruits like lemons and oranges, peppers, berries like blueberries and blackcurrants and leafy green vegetables.

Vitamin A deficiency impairs innate immunity by preventing the regeneration of mucosal barriers damaged by infection, and by diminishing the function of neutrophils, macrophages, and natural killer cells. Vitamin A is found in the diet in 2 forms -retinol, in eggs, butter, liver and full fat dairy, and beta carotene. Foods that are high in the colourful carotenoids — carrots, sweet potatoes, pumpkin, cantaloupe and squash — are all good sources of beta carotene. The body turns these carotenoids into vitamin A, and they have an antioxidant effect to help strengthen the immune system against infection.


Vitamin D is also known to help our immune system. It supports the antimicrobial properties of immune cells and upregulates the immune response. Although some vitamin D is found in foods like oily fish and egg yolks, the main source of vitamin D is the sun which helps our skin produce this essential vitamin. In the UK, the angle of the sun from October to March, prevents the manufacture of Vitamin D so it is a good idea to take a supplement through these winter months. Check your levels either through your GP or through a private testing service like BetterYou.

Zinc is another nutrient know to support the immune system. Many studies show that low zinc levels are linked with pneumonia in the elderly so, as the COVID -19 virus may lead to pneumonia,  it makes sense to ensure we have adequate levels.. You will need to take in regular amounts of zinc as the body does not store it. You ll find zinc in shellfish, meat, dark poultry meat, chickpeas, lentils and pumpkin seeds.

Selenium is also an essential nutrient that helps to produce anti-oxidants in the body. You can ensure good levels by eating brazil nuts, wholegrains like oats, turkey, sunflower seeds and dairy.

Prebiotic and probiotic foods. Seventy percent of your Immune system lives in your gut. Millions of bacteria viruses and fungi live there and help educate and support our Immune system. The essential task of the immune system is to maintain a balance between reaction and tolerance, and it is essential that this tolerance, is established. A diverse gut flora established in early life with many types of bacteria, fungi, and other microorganisms, is crucial for this, as it teaches the cells of the immune system how to react to each and every molecule to which  it is exposed

Since the  balance of bacteria in our gut influences the balance of our immune system, an unbalanced bacterial flora with for instance too many pathogens can shift the immune system to an increased inflammatory state with a so-called “leaky gut”.

So support your beneficial gut bacteria with prebiotic foods like asparagus, leeks and onions, which provide food for them to ‘eat’, so that they can make helpful B vitamins and short chain fatty acids which support the integrity of your gut lining, so preventing your gut lining from becoming hyper permeable. You should also eat fermented foods like yoghurt, kefir, apple cider vinegar and sourdough bread which add beneficial bacteria to your gut.

What foods you can eat to help your Immune System?

Eating a healthy wholefood, unprocessed balanced diet of vegetables, fruits, wholegrains, nuts, seeds eggs oily fish and lean proteins is the best long-term help you can give your Immune System. However, there are also so-called  ‘superfoods’ which can give your immune system that extra boost.

Brightly coloured fruit


Fruit is full of important vitamins and minerals that keep your immune system healthy. Kiwi fruits and oranges are high in Vitamin C  which helps to protect and maintain healthy cells and tissues. As a result of this your body will be more able to defend itself from colds and flu, plus eating these foods could reduce the length of any illness. As well as kiwi and oranges, strawberries, blueberries, acai and goji are also full of vitamin C

Brightly coloured vegetables

Colourful vegetables are beneficial too. These are another great source of vitamin C and antioxidants which, help to keep the immune system strong.

Red bell peppers are particularly high in vitamin C – in fact they actually contain more than many citrus fruits!.. Try making a tasty soup, with roasted peppers and tomatoes, another great Vitamin C source 

Green, leafy vegetables

Broccoli, spinach and kale are a fantastic source of vitamins and minerals so should definitely be part of your diet. These three foods are particularly rich in Vitamins A and E and that all-important C. Remember though, these things are lost if the veg is

cooked too much so keep your greens firm in order to retain as much goodness as possible

Other vegetables

Diversity is key. Eating a wide range of fruit and vegetables will provide your body with a good mix of nutrients. Mushrooms for example, contain the polysaccharide beta glucans which encourage the production of infection-fighting cells and also improve the action of white blood cells. White blood cells are cells of the immune system that work to protect the body from infection and viruses.


Sweet potatoes are also beneficial as these are high in Vitamin A which helps to improve your skin. As your skin is the first line of defence against bacteria it is worth looking after it! 


This might not be the most obvious addition to this list, but oats have an antioxidant effect, are high in Vitamin B and have been shown to boost immunity! They also provide fibre which can add to your daily intake of prebiotic foods. You can have a nice bowl of porridge or overnight oats for breakfast to give yourself a good immune boosting start to the day.

Nuts and seeds

Nuts and seeds are also important for the immune system. Nuts such as almonds, hazelnuts, peanuts and walnuts are rich in minerals such as zinc which is vital for maintaining the normal function of cells within the immune system. As already mentioned, a selenium deficiency can have a negative effect upon the Immune system, so a handful of nuts a day should help to keep your levels up.


Yoghurt and Kefir


These are packed full of live cultured bacteria or ‘friendly bacteria’ – the Probiotics. These help your digestion absorb as many nutrients as possible and give your immune system the support it needs to fight off bugs. Adding some dark berries to your yoghurt adds immune boosting vitamins too!

Garlic and ginger

These add a distinctive flavour to meals and are also beneficial for your immune system. There’s plenty of research about the way these help to fight infection and support the immune system. Try a warming ginger tea at the first sign of a sniffle

Obviously eating all these immune supporting foods is absolutely no guarantee that you will be able to eat your way to avoiding these viruses. However, a healthy diet rich in vitamin and mineral rich vegetables, fruits, and good proteins may well help you recover your health more quickly if you do succumb.







Tomato, red pepper and sweet potato soup with harissa yogurt


1 large sweet potato, peeled and cubed 
4 pointed red peppers, roughly chopped or 2 standard red peppers
2 red onions, roughly chopped 
300g small plum tomatoes (or a 440g tin)
2 garlic cloves 
1 red chilli, deseeded 
4 tbsp olive oil 
800ml fresh vegetable stock 
1 tsp sweet smoked paprika 
2 tsp harissa 
4 tbsp Greek or other natural yogurt 
1 tbsp chopped chives 
4 small slices sourdough bread, to serve


1. Preheat the oven to 200˚C, gas mark 6. Put the sweet potato in a large roasting tin with the peppers, red onions, tomatoes, whole garlic cloves and chilli; season and toss with the olive oil. Roast for 30 minutes.

2. Transfer the contents of the tin to a large pan with the vegetable stock and bring to the boil, then reduce the heat and simmer for 5 minutes until the sweet potato is cooked through. Add the smoked paprika and season. Use a stick or jug blender to whizz until smooth.

3. Ladle the soup into bowls. Gently fold the harissa into the yogurt and dollop a little on top of each one. Scatter over some chives and serve immediately, with the bread on the side

Full of vitamins A and C , as well as the immune supporting  plant chemical quercetin. The sourdough and yoghurt will support your gut bacteria to help them manage your immune system.