In the past year, we’ve realised more than ever that having our immune systems in fine fettle puts us in the best position to fight off nasty infections like Covid.
Since the pandemic began, interest in nutrition and diet in relation to immunity has increased, reports the British Nutrition Foundation (BNF). But misconceptions surrounding this are rife.
The immune system is a complex network of cells and chemical compounds that helps defend the body against infections – and it’s not something that can be ‘boosted’ or ‘supercharged’. Dr Jenna Macciochi, an immunologist based at the University of Sussex, previously told HuffPost UK people mistakenly talk about the immune system as a binary of “weak” or “strong”.
Instead, it represents a “hugely complex dance that’s happening between many different components”. She likened it to an orchestra: “It all has to play together for the song to sound correct. If one of the instruments is screeching in the background, it knocks everything else out.”
While you can’t boost your immune system to work at 110% – or make yourself magically immune to Covid-19 – you can support it to function at its fullest. And potentially, this could help reduce the severity of coronavirus if you caught it, or help you recover better, explained Dr Macciochi.
So how can you do that? Well, eating a balanced diet to ensure you’re not deficient in key nutrients is one way. A number of different nutrients – including protein, omega-3 fats and many vitamins and minerals, found in a wide range of foods – are involved in supporting our immune systems to work normally.
Sara Stanner, science director at BNF, says there’s no single nutrient or food that can ‘boost’ immunity, so wherever possible, these vitamins and minerals should come from a nutritionally-balanced and diverse diet. Variety is the spice of life – and very important to your immune system.
Here are just some of the vitamins and nutrients you should be adding into your diet to help your immune system do its thing, according to the BNF.
The vitamin has several important functions in the body, including helping the immune system work properly, improving vision and keeping skin healthy.
It’s found in eggs, cheese and liver. The body can also make vitamin A from beta-carotene which is found in dark green leafy veggies like spinach and orange-coloured fruits and vegetables like carrots, sweet potatoes and butternut squash.
Copper helps the body to produce red and white blood cells, and triggers the release of iron to form haemoglobin, the substance that carries oxygen around the body. It’s also thought to be important for infant growth, brain development, the immune system and strong bones, according to the NHS.
Wholegrain breakfast cereals, wholewheat pasta, quinoa, prawns, dried fruit, nuts, and pulses such as beans, chickpeas and lentils are all good sources of copper.
Vitamin B6 helps the body use and store energy from protein and carbohydrates in food, while also helping the body to form haemoglobin.
It’s found in chicken, turkey, bananas, avocados, plantains, walnuts, cashews and sesame seeds.
Folate is a type of B vitamin. The vitamin helps the body form healthy red blood cells and can reduce the risk of birth defects, such as spina bifida, in unborn babies. As such, pregnant women are often advised to take folic acid, which is its synthetic form.
Folate is found naturally in green vegetables like broccoli, cabbage, and spinach, as well as in chickpeas, oranges, berries, cheese and wholemeal bread.
Another important B vitamin. This one’s responsible for helping the body: make red blood cells, keep the nervous system healthy, release energy from food and use folate. If you don’t get enough of it, you could end up with vitamin B12 deficiency anaemia.
The vitamin is found in meat, fish, milk, cheese, eggs, fortified yeast extract, fortified breakfast cereals and fortified milk alternatives (e.g. soya, oat, almond drinks – check the labels to make sure they have it).
Iron is important in making red blood cells, which carry oxygen around the body. A lack of it can lead to iron deficiency anaemia, signs of which can include: tiredness, lack of energy, shortness of breath, heart palpitations and pale skin.
Iron is found in red meat, kidney beans, lentils, nuts and nut butters, seeds and seed pastes (such as tahini), wholemeal bread and dried fruit like apricots.
This vitamin does loads for our bodies, including helping to protect cells and keeping them healthy; maintaining healthy skin, blood vessels, bones and cartilage; and helping with wound healing.
We often associate vitamin C with oranges or orange juice, but there are plenty of other foods that contain this gem of a vitamin. These include: grapefruit, strawberries, kiwi fruit, cabbage, kale, spinach, cauliflower, red and green peppers and tomatoes.
Selenium plays critical roles in reproduction, thyroid hormone metabolism, DNA synthesis, and protection from oxidative damage and infection, according to the National Institutes of Health in the United States.
It’s found in nuts and seeds – particularly Brazil nuts, cashews, sunflower seeds – as well as eggs, poultry, fish and shellfish.
Often known as the sunshine vitamin, vitamin D helps regulate the amount of calcium and phosphate in the body, which keeps bones, teeth and muscles healthy.
It can be found in some foods, such as: oily fish (salmon, sardines, herring and mackerel), red meat, liver, eggs (specifically the yolks), some fortified breakfast cereals, and some fortified dairy and dairy alternatives.
Sometimes it can be hard to get all the vitamin D you need from food sources and daylight, in which case it might be worth taking a daily supplement. This is advised for people who spend long periods indoors, wear clothes that cover all or most of their skin, and for anyone with an African, African-Caribbean or south Asian background who may not make enough vitamin D from sunlight alone.
Last but in no way least, zinc has many useful functions. It’s crucial for immune function and wound healing, but also helps us maintain our sense of taste and smell; regulate insulin production, storage, and release; and assists in thyroid function (among other things).
The micronutrient is found in a range of foods including: red meat, poultry, cheese, crab, mussels, pumpkin seeds, pine nuts, wholegrain breakfast cereals, and wholegrain and seeded breads.