It is my belief that the foods we consume, the environments we inhabit and the relationships we hold, have a profound effect on our ability to achieve health, prevent chronic illness and improve the life in our years.
That being said, the spread of COVID-19/coronovirus this past year is taking it’s toll on our dietary efforts, our relationships and our environments! Which is unfortunately a necessary evil BUT affecting our ability to achieve/maintain health due to stress, convenience foods, restricted environments and separation from family and friends. However, I do believe in our ability to achieve better health through COVID or post COVID, we just have to look in the right place and for me that starts with our Immune system.
The human immune system is a highly complex system and possesses extensive ‘plasticity’ in its ability to respond to pressures brought to bear on it by infectious diseases, host microbes and food availability. However, this evolutionary plasticity can be compromised by stress, dietary overindulgence and natural aging which can result in an imbalance or dysregulation of immune function. During a pandemic, this may mean worse symptoms, a greater risk of infection and / or poor recovery.
So how can we favorably modulate our immune function, not only to reduce the chance of infection but for potentially reducing the severity of and consequences from infections? It might be helpful to consider some or all of the following diet and lifestyle recommendations to help bolster your immune function.
Vitamin C – Vitamin C may help to prevent infections, including those caused by bacteria and viruses. Regularly administered vitamin C has been shown to shorten the duration of colds, and higher doses of vitamin C during an illness can also act as a natural antihistamine and anti-inflammatory. The best sources of vitamin C from foods are: red peppers, oranges, kiwi’s, broccoli, cauliflower, green peppers and citrus fruits among others.
Vitamin D – vitamin D is thought of as a hormone rather than a vitamin and it’s role is to absorb calcium from the gut into the bloodstream. It’s also one of the most powerful and important nutrients for supporting our immune system. Unfortunately, we don’t get a lot of vitamin D from the sun in Ireland from September through to April so, a high percentage of the population are deficient. As stated by D.M. McCartney and D.G. Byrne, vitamin D deficiency is associated with an increased risk of acute viral respiratory infection and community acquired pneumonia, with several molecular mechanisms proposed to explain this association. Vitamin D supplementation has also been shown to reduce the risk of respiratory infection. So, it’s recommended to get your levels checked with your GP and increase your vitamin D-rich foods or supplement, if required. Food sources of vitamin D include; oily fish (salmon, sardine, herring, mackerel), liver, egg yolks, fortified foods such as spreads and cereals.
Vitamin A – Vitamin A is a fat-soluble vitamin and increases resistance to infection, by enhancing phagocytes, antibody production and mucosal barriers, among others. For short-term use and particularly for those with moderate vitamin A deficiency, supplementation can be extremely helpful in supporting the body’s ability to fight infections, particularly with regard to respiratory infections. Alternatively, food sources of vitamin A include; real butter, fish liver oils (salmon, halibut, cod), liver, egg yolks, green leafy vegetables and carrots among others.
Zinc – Zinc is a mineral and plays a significant role in supporting our immmune health as it activates over 200 different enzymes in the body. For example, zinc can help to reduce the frequency of infections as well as the duration and severity of the common cold when taken within 24 hours of onset. Food sources of zinc include; beef, peppers, egg yolks, ginger, herring, liver, lamb, oysters, sea food, sunflower and pumkin seeds and wholegrains.
Selenium – Selenium, a key nutrient for immune function and it’s also an antioxidant that helps boosts the body’s defenses against bacteria, viruses, and cancer cells. It may particularly help to protect against certain strains of flu virus. Selenium is easily obtained from foods, with the richest source being Brazil nuts but is also found in broccoli, organ meats, mackerel, eggs, fish, garlic, liver, wholegrain cereals and celery.
Aside from looking at specific nutrients to support immune health (of which there are several others) it’s important to look outside of your diet as well to certain lifestyle practices that are vital to our overall health and wellbeing. These include things like proper sleep hygiene habits, daily exercise or movement techniques, stress-reduction techniques (journalling, meditation, diaphragmatic breathing etc.) and scheduling things into your day that bring you joy (e.g. dancing in the kitchen, calling a friend, sitting in the garden to enjoy your lunch, going for a walk – whatever this looks like for you) for that all important nervous and immune sytem support.
In happiness and health, you are what you eat.
For further information book a 15min call with Orla Mc Laughlin to discuss any nutrition or dietary issues you may be experiencing and we’ll ensure you get the RIGHT nutrition programme to suit your needs. https://calendly.com/healthbyorla/15min
*This article is only intended to identify nutrients that may support your immune system health. It is not medical advice or intended as treatment recommendations. Always consult your GP or healthcare provider. For up-to-date information on COVID-19, please visit www.hse.ie
- IFM Medical Education Team. July 2020. Boosting Immunity: Functional Medicine Tips on Prevention & Optimizing Immune Function During the COVID-19 (Coronavirus) Outbreak. Accesssed, 01/02/2021. https://www.ifm.org/news-insights/boosting-immunity-functional-medicine-tips-prevention-immunity-boosting-covid-19-coronavirus-outbreak/
- Bergman P, Lindh AU, Björkhem-Bergman L, Lindh JD. Vitamin D and respiratory tract infections: a systematic review and meta-analysis of randomized controlled trials. PLoS One. 2013;8(6):e65835. doi:10.1371/journal.pone.0065835
- Biesalski HK, Nohr D. Importance of vitamin-A for lung function and development. Mol Aspects Med. 2003;24(6):431-440. doi:10.1016/s0098-2997(03)00039-6
- Common colds: protect yourself and others. Centers for Disease Control and Prevention. Reviewed February 11, 2019. Accessed February 01, 2021. https://www.cdc.gov/features/rhinoviruses/index.html
- Phytonutrients. NutritionFacts. Accessed February 01, 2021. https://nutritionfacts.org/topics/phytonutrients/
- Steinbrenner H, Al-Quraishy S, Dkhil MA, Wunderlich F, Sies H. Dietary selenium in adjuvant therapy of viral and bacterial infections. Adv Nutr. 2015;6(1):73-82. doi:10.3945/an.114.007575
- Osiecki H. The Nutrient Bible. Seventh edition. Australia: Bio Concepts Publishing, 3-161.
- Nicolle L., Woodriff Beirne A. (2010). A Practitioner’s Handbook. Biochemical Imbalances in Disease. London: Singing Dragon, 256-297.