We keep social distance.
We wear our masks.
All in an attempt to help manage the spread of illnesses as the world is at war with the COVID-19 pandemic.
Added to this, it is great to know that our body is adapted perfectly with its own natural defence system to fight off invading viruses, bacteria and other germs that cause illness and infection: the immune system.
What is the Immune System?
The immune system is the body’s natural defence, working 24/7 to protect the body.
The immune system is much like an army, with its soldiers (like immune cells like lymphocytes, macrophages, and natural killer cells) always on standby to defend the battlefield.
- The innate immune system works quickly, within minutes to hours, to help identify and destroy invading pathogens. The innate immune system is made up of physical barriers (like the skin and gut), as well as other biochemical measures that enhance the action of antibodies, white blood cells, and the inflammatory responses needed for immunity. 1,2
- The second type of immune response is called the adaptive immune system. The adaptive immune system is much slower to respond compared to the innate immune system. This system uses white blood cells like B lymphocytes, T lymphocytes, immunoglobulins, and other body fluids, and is responsible for the immune system’s “memory” so that if we are infected again by the same pathogen, there is a very quick and targeted attack by the immune system. 1,2
How Can I Support my Immune System?
In times when so much feels out of our control when it comes to protecting our bodies from illness and infection, it is great to know that good nutrition plays a huge role in keeping our immunity in tip-top shape.
A healthy and balanced diet that includes a variety of foods means you will get in a variety of nutrients.
Here are some of the key nutrients known to be essential for optimal immune support:1
- Vitamin A: The skin is our body’s first line of defence against invading bacteria and viruses, so understandably the skin can provide great support to our immune system. Our skin needs vitamin A for the normal functioning of the immune system.
Butternut, pumpkin, and carrots are examples of foods that contain beta-carotene, which the body converts into vitamin A. Beef or chicken liver is also a cost-effective source of vitamin A.
- Vitamin C: It is well-known that vitamin C is important in keeping the immune system strong.3 Vitamin C acts by protecting the body cells from damage, also supporting the normal function of the skin. The body cannot make or store vitamin C, so it needs to be eaten regularly. Winter favourites like naartjies and oranges are a good source of vitamin C, as are strawberries, paw paw, mango, kiwi, sweet peppers, and broccoli.
- Vitamin D: Vitamin D also contributes to the normal function of our immune system. In fact, new research has shown that vitamin D may lower the risk of flu and COVID infections and death.4 The best way to get some vitamin D is from the sun as the skin can make vitamin D from sunlight. You can also get a bit of vitamin D from food like tinned fish like pilchards (especially if you eat the bones). Mushrooms also have some vitamin D. In fact, if you put your mushrooms in the sun for 15 min this increases the vitamin D by 10 – 30 times.
- B-vitamins: The group of B-vitamins [especially vitamin B6 (pyridoxine), vitamin B9 (folate) and vitamin B12 (cobalamin)] contribute to the normal function of the immune function. B6 is found chicken, fish, oats, bananas, and peanuts. Folate is found naturally found in green leafy vegetables, nuts, and beans, and vitamin B12 is found in all animal foods, like meat, chicken, fish, eggs, and dairy.
- Zinc: Zinc is found in almost every cell of the body. Zinc is an essential mineral that is not made nor stored in the body, which means that we need to eat zinc-rich foods to meet our needs. Zinc supports immunity and wound healing,5 so it is concerning that two in ten people don’t get in enough zinc.6 Affordable zinc-containing foods are beef, baked beans, porridge, and chicken pieces, with some yoghurts in SA now made with added zinc.
- Copper plays a role in the functioning of special immune cells like macrophages, neutrophils, and monocytes. Copper also enhances the activity of natural killer cells, which help to limit the spread of infections in the body. New evidence shows that copper may have the potential to kill viruses like the Corona virus.7 Avocados are high in copper, with one serving of avocado offering up one third of our daily copper needs.
While not a nutrient per se, fibre can also indirectly support our immune system.
This is because a whopping 65% of our immune system is found in the gut8 and we know that fibre improves the health of the gut.
Unfortunately, many South Africans fall short9 of their daily fibre intake.
Fibre is found in plant-based foods such as fruit, vegetables, legumes, and wholegrains.
Our immune systems work best during the time we sleep10, so aim for a healthy bedtime routine.
Being active11 has also been shown to improve the body’s defence system.
It is important to remember that as much as healthy eating is very important, it does not take away the need for good hygiene measures like regular handwashing/sanitising and covering your mouth when coughing or sneezing.
The FitChef Difference
Our FitChef meals, made from real, whole food like fruit, vegetables, and high fibre grains, are packed with immune supporting nutrients and fibre.
- Gombart et al; A review of micronutrients and the immune system working in harmony to reduce the risk of infection. Nutrients, 2020;12:236.
- Calder PC, Carr AC, Gombart AF, Eggersdorer M. Optimal nutritional status for a well-functioning immune system is an important factor to protect against viral infections. Nutrients. 2020;12:1181.
- Hemila H, Chauker E. Vitamin C for preventing and treating the common cold. Cochrane Systematic Review- Intervention Version. 2013. DOI: 10.1002/14651858.CD000980.pub4
- Grant WB et al. Evidence that Vitamin D Supplementation Could Reduce Risk of Influenza and COVID-19 Infections and Deaths. Nutrients 2020, 12, 988.
- Wessels I et al. Zinc as a gatekeeper of immune function. Nutrients. 2017;9:1286.
- Wessells KR, Singh GM, Brown KH. Estimating the Global Prevalence of Inadequate Zinc Intake from National Food Balance Sheets: Effects of Methodological Assumptions. PLoS One. 2012;7(11): e50565. Doi: 10.1371/journal.pone.0050565.
- Raha S et al. Is copper beneficial for COVID-19 patients? Medical Hypotheses. 2020;142: 109814.
- Mayer EA, Tillisch K, Gupta A. Gut/brain axis and the microbiota. Journal of Clinical Investigation. 2015;125(3):926–38.
- Mchiza ZJ et al. A Review of Dietary Surveys in the Adult South African Population from 2000 to 2015. Nutrients. 2015;7:8227-50.
- Irwin M, Opp M. Sleep Health: Reciprocal Regulation of Sleep and Innate Immunity. Neuropsychopharmacology.2017;42, 129–555. https://doi.org/10.1038/npp.2016.148
- Nieman DC, Wentz LM. The compelling link between physical activity and the body’s defence system. Journal of Sport and Health Science, 2019;8(3):201-17.