Immunity Supporting Nutrients
Over the past few months we’ve all become more aware of the importance of our immune system and its role in defending us. Whilst we can’t necessarily boost or increase our immunity we can take an active role in supporting it.
So, how can we ensure our immune system is functioning at its best? We’ve picked the brains of our Nutrition Team to get you the inside scoop on the key nutrients and foods that support a strong immune system:
Zinc
Zinc is a mineral which is involved in influencing the growth and development of the immune system. Zinc is crucial for normal development and function of cells mediating innate immunity, white blood cells and Natural Killer (NK) cells, which act to control viral infections (1). What is innate immunity you ask? Innate immunity refers to the body’s defence mechanisms that get to work when an antigen (the bad guys) enter your system.
Where can you find it?
Zinc is highest in protein rich foods, like seafood, meats, poultry and liver. If you are vegetarian or vegan, you can get zinc in the form of legumes, whole grains, nuts and seeds. It’s important to know that there are certain factors that can reduce the absorption of zinc, such as ‘anti-nutrients’ found in legumes: The trick is to soak your beans overnight, discard the water, and then cook them in fresh water- this will remove phytates (anti-nutrients) and increase the absorption capability of zinc into the body.
Selenium
This nutritional antioxidant strongly influences inflammation and immune responses (2). Selenium is actually an essential mineral, meaning it must be obtained through our diet. It helps lower oxidative stress in your body, which reduces inflammation and in turn enhances immunity. Oxidative stress can be caused by lifestyle factors, such as smoking, alcohol, toxins and stress.
Where can you find it?
Foods rich in selenium include brazil nuts, fish, meats, eggs, brown rice, dairy products, sunflower seeds, mushrooms, lentils and oats. A single Brazil nut contains 68 to 91 micrograms (mcg) of selenium, meaning that just one nut per day can provide the daily recommended adult allowance of 55 mcg. Due to this, intake of brazil nuts should actually be limited to a couple of times a week.
Vitamin C
Vitamin C, also known as ascorbic acid, is a water soluble vitamin that is essential for the growth and repair of connective tissues, bone, cartilage, blood vessels and skin. Vitamin C supports cell-mediated immune responses; this means it activates protective responses- think of them like your first line of defence, when you're body is under attack from a foreign invader these protective responses kick into action to fight the bad guys. It has been researched that Vitamin C deficiency can lead to reduced resistance to certain pathogens, while a higher supply strengthens parts of the immune system (3).
Where can you find it?
As Vitamin C is not made in the body; we need to obtain it from external sources, such as limes, lemons, oranges, strawberries, guava, kiwi fruits, papaya, spinach, kale, tomatoes, bell peppers, broccoli, blackcurrants and brussel sprouts.
Vitamin A
Vitamin A is crucial for maintaining vision, promoting growth and development, and protecting mucus integrity in the body- sounds gross but mucus is very important, especially when it comes to defending our bodies. It is known as an anti-inflammatory vitamin because of its role in enhancing immune function (4).
Where can you find it?
Vitamin A is found as preformed vitamin A in foods such as liver, cod-liver oil, butter, eggs, and dairy products, and as provitamin A carotenoids (beta carotene) in foods such as spinach, carrots, and orange fruits and vegetables.
Vitamin D
We’ve been hearing a lot about Vitamin D when it comes to immunity recently. But why is it so important? Well, Vitamin D can act to modulate immune responses - this means it helps to keep your immune system in check. Deficiencies in Vitamin D are associated with increased autoimmunity, as well as an increased susceptibility to infection (5).
Also known as the ‘sunshine vitamin’, Vitamin D is made when your skin gets enough direct UV light from the sun. We can also get Vitamin D through our food intake, however the sun is the most potent source. A lot of us are spending more time indoors whilst we work from home so it’s really important to make sure we are getting enough Vitamin D. A good quality Vitamin D supplement will help in keeping your levels in the optimal range.
Where can you find it?
Foods rich in vitamin D include oily fish (mackerel, sardines, herring, salmon, sardines), red meat, liver, egg yolk, some fortified bread and cereals and mushrooms.
The immune system is a host defence system, protecting us against invaders like pathogens, harmful bacteria and viruses. It is important to know that we can positively affect our health with these key nutrients, that can support us and our immune response.
If you fancy some further reading: Here are our references:
1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2277319/
2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3723386/
3 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5707683/
4 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6162863/
5 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3166406/