Supporting your immune system to fight off infections and illnesses is a continuous journey, not something we can just do for a while and then forget.
How to boost your immune system
Diet is one of the key components for a healthy immune system. The good news is it doesn’t need to be tasteless or boring. Eating a healthy, nourishing diet rich in immune boosting foods can be fun, enjoyable and easy too.
Too much salt weakens the immune system
Recent research(1) has shown that a diet high in salt is not only bad for your blood pressure but for your immune system too. The excess salt may inhibit the function of the most common immune cell in the blood, granulocytes. These are scavenger cells that attack bacteria and if they are not doing their job sufficiently infections may proceed more severely.
The WHO(2) recommends for adults to eat less than 5 grams (around a teaspoon) of salt (sodium chloride, 2000mg of sodium) per day. Studies(3) have shown that Australians eat around 9 grams of salt per day, nearly double the recommended amount. So, what can we do? Reduce our salt and flavour our food another way.
The salt shaker is often the first thing people reach for to flavour food, however we have so many other wonderful, tasty herbs and spices to play with. They not only add flavour but they bring with them plenty of phytochemicals, compounds that have antioxidant activity which research(4) shows can improve immune system function.
Adding fresh herbs such as parsley, coriander, rosemary, basil or sage, many that can be grown easily at home, add taste and nutrients to our food. The small quantities add up over the days as too does the less salt you will use.
Many herbs and spices have been used in traditional medicine for centuries, such as turmeric, garlic and ginger. Modern science(5) supports the use of many of these, including ginger’s anti-inflammatory and anti-oxidative benefits, which may support the immune system. Ginger can be enjoyed in many ways in; a warm drink, adding a kick to a smoothie, in a bowl of soup or a stir fry.
So before you grab the salt shaker, experiment with other ways you can add flavour. This is an easy way to help support the immune system.
Healthy fats and their importance to the immune system
The oil you use can make a difference to your health and help boost the immune system. Fresh extra virgin olive oil provides important polyphenols that other refined oils often don’t have. These have antioxidant activity to help fight against inflammation(6). Choose fresh extra virgin olive oil and note, it can be used in all of your cooking, even at high temperatures.
Healthy fats are also found in nuts. A handful a day(7) might just help keep the doctor away! Nuts are a good source of zinc, putting them up there with foods that boost the immune system.
Avocados are an important source of healthy fat, antioxidant compounds and also provide important nutrients that help support our immune system, such as vitamin C, E and beta-carotene. Healthy fats help the body absorb some of these important nutrients, particularly fat-soluble nutrients such as vitamins A, D, E and K(8).
Including healthy fats in your diet is not hard to do and it also adds flavour. Think about how delicious crispy roast vegetables drizzled with extra virgin olive oil and a sprinkle of fresh herbs such as rosemary taste.
Vitamin C for the immune system
We all know how important vitamin C is to support immune health, but did you know your body doesn’t store it? We need to get a regular dose of vitamin C for immunity support which the good news is, it is not hard to do. Many of our fresh fruit and vegetables are plentiful in vitamin C and you can generally get your daily dose with 2 fruit serves a day of these immune-boosting foods, including kiwifruit, strawberries, oranges, lemons, mandarins and blackcurrants just to name a few. Vegetables can have plenty of vitamin C too, red capsicum is one of the highest vitamin C containing foods and broccoli, Brussel sprouts and cabbage are also good sources. Vitamin C helps with the absorption of iron from plant foods, with iron being an important nutrient for the immune system too.
Adding fresh fruit to your shopping list and cutting up fruit so it is ready for the family to grab and go are easy ways to make it easier to have your two serves per day.
What are signs of a weak immune system?
Signs of low immune system health include regular colds and infections that you can’t shake off, frequent digestive issues (such as diarrhea, gas or constipation), low energy, high stress levels, and wounds that are slow to heal.
What tea is good for the immune system?
As well as providing the sensorial comfort of a soothing hot drink, some teas are infused with ingredients that have been shown to provide immune support. Green tea, ginger tea, and chamomile tea have all been shown to boost immune system health (9).
Do supplements actually boost the immune system?
Supplements can provide your body with the tailored nutrients it needs to support immune system health when dietary intake is inadequate. Importantly, they must be taken as part of a holistic approach to a healthy lifestyle, alongside a balanced diet and regular exercise. As nice as it would be to sit on the couch and pop a supplement while eating ice cream, that’s sadly not how it works!
When considering how to support the immune system, remember that there are many areas where diet plays an important part, this is an ongoing journey!
References:
- Katarzyna Jobin, Natascha E. Stumpf, Sebastian Schwab, Melanie Eichler et al A high-salt diet compromises antibacterial neutrophil responses through hormonal perturbation. Science Translational Medicine, 2020 DOI: 10.1126/scitranslmed.aay3850
- https://stm.sciencemag.org/content/12/53. 6/eaay3850
- https://www.who.int/news-room/fact-sheets/detail/salt-reduction#:~:text=For%20adults%3A%20WHO%20recommends%20that,salt%20per%20day%20(1).
- https://www.heartfoundation.org.au/Heart-health-education/Salt-and-heart-health
- https://www.ingentaconnect.com/content/ben/ctmc/2011/00000011/00000014/art00002;jsessionid=2sq7qffp9gqb.x-ic-live-02
- Mashhadi NS, Ghiasvand R, Askari G, Hariri M, Darvishi L, Mofid MR. Anti-oxidative and anti-inflammatory effects of ginger in health and physical activity: review of current evidence. Int J Prev Med. 2013;4(Suppl 1):S36-S42.
- Aparicio-Soto M, Sánchez-Hidalgo M, Rosillo MÁ, Castejón ML, Alarcón-de-la-Lastra C. Extra virgin olive oil: a key functional food for prevention of immune-inflammatory diseases. Food Funct. 2016;7(11):4492-4505. doi:10.1039/c6fo01094f
- NHS. Fat: The Facts. https://www.nhs.uk/live-well/eat-well/food-types/different-fats-nutrition/ Sourced 25 August 2019
- https://www.nutsforlife.com.au/resource/are-nuts-anti-inflammatory/
- Harvard Medical School. The health benefits of 3 herbal teas. https://www.health.harvard.edu/nutrition/the-health-benefits-of-3-herbal-teas Published 21 October 2021.
