Due to the events of the past year, you've probably heard the word 'immunity' more than ever before, and whilst this may be said in different contexts, there has been A LOT of talk about how to 'boost' our immune system to reduce the risk of illness and disease. The fact of the matter though is that we can’t ‘boost’ our immune system through our diet and lifestyle choices, we can only SUPPORT it.
Whilst there’s no silver bullet or single food or nutrient that will provide us with immunity to disease, what we can do is support our health, by eating a varied, balanced diet to meet our nutritional requirements and living a healthy lifestyle.
Nutrients to support a healthy immune system
Whilst there’s no silver bullet or single food or nutrient that will provide us with immunity to disease, what we can do is support our health, by eating a varied, balanced diet to meet our nutritional requirements and living a healthy lifestyle.
Vitamin A - Vitamin A plays an important part in our immune health by keeping the membranes in our nose and throat healthy, which are the body’s first line defences to protect us against harmful bacteria. There are two forms of Vitamin A, retinol, which is found in foods such as liver, pate, eggs, cheese, fortified spreads as well as oily fish, and beta-carotene (which is then converted into retinol), which we can find in foods such as carrots, apricots, mangoes, and other brightly orange and yellow coloured produce.
Vitamin C - Vitamin C seems to be the nutrient we most commonly associate with our immune system, and although it’s contrary to popular opinion, there is no evidence that it can prevent or cure a cold. However, it can work to support the production of white blood cells, support healthy skin, bones and cartilage, and support wound healing. It’s very easy to obtain our Vitamin C requirements for the day through eating a variety of produce such as citrus fruits, berries, broccoli, kiwi - we can even meet this through eating just a quarter of a medium sized bell pepper.
Zinc - Similar to Vitamins A and C, zinc plays an important role in the wound healing process, and keeping our cell membranes healthy. Sources of zinc within the diet include shellfish, fortified bread and cereal products, meat, nuts, seeds, eggs and dairy.
Vitamin D - Throughout the months of October - April, we should all be taking a 10mcg Vitamin D supplement to support our immune system and reduce the risk of infection. This is because the sun’s UVB rays are not strong enough to synthesise Vitamin D in our skin throughout the Winter months, and it is challenging to obtain sufficient amounts through our diet everyday. We can of course still include sources of Vitamin D within the diet though, such as oily fish, eggs, and mushrooms (grown in certain conditions).
Lifestyle factors to support a healthy immune system
Exercise - Exercise plays an important part in keeping our immune system healthy by encouraging our immune response, promoting our cardiovascular health, reducing stress and risk of non-communicable diseases such as type 2 diabetes, heart disease and some cancers. We should be aiming for 150 minutes of moderate intensity exercise per week such as a brisk walk, gentle jog, swim or bike ride, or 75 minutes of more vigorous intensity exercise such as circuit training, fast running or cycling, OR we can do a mix of both! To protect our bones, joints and muscle health, we should also aim to undertake two sessions of resistance activity such as bodyweight exercises, yoga, pilates or weight-lifting.
Sleep - Getting a good nights’ sleep is one of the most important things we can do for our immune health. Research has shown that a regular lack of sleep, or regular poor quality sleep can reduce our immune response and increase the risk of infection and disease. We should be aiming for 7-9 hours of good quality sleep per night. Switching off electronics before bed, having a structured wake-up/bed-time routine and getting out for a daily walk or exercise can all help to improve sleep quality.
Stress - Whilst short-term stress isn’t necessarily a bad thing (we need it for our fight/flight response!) Chronic stress (for a long period of time) can increase the production of cortisol, which over time can weaken the activity on the immune system. Although reducing stress can be easier said than done, activities that can help to reduce stress include meditation and mindfulness, going for a walk, talking to a friend, having a bubble bath, or whatever makes you feel good! Try to prioritise some ‘you time’ every-day to reduce prolonged stress.
Hopefully by reading this, you will soon realise that there are many different factors when it comes to protecting and supporting our immune system, and it’s not as simple as an ‘immune boosting’ drink or supplement! If you are uncertain about whether you are obtaining all your nutritional requirements through your diet, then a multivitamin can act as a ‘safety blanket’ - especially if you have a list of foods you don’t usually eat. However, food first is always best! Nutrients work in combination with each other to support a healthy immune system, so aim for a variety of colours when it comes to your fruits and vegetables especially!