Optimising the Immune System

There is increasing evidence that being in a good state of health is one of best ways to protect yourself from succumbing to a severe COVID-19 infection and many other infections.  Given that there is no vaccine that is proven to give lasting protection, and the drugs that are currently used are not always effective we all need to be proactive in optimising our health.

Things we’ve learnt from the COVID-19 pandemic so far include:

• Drugs and vaccines take time to produce, test and distribute so may not be the best or only way to deal with a novel global pandemic.
• People with underlying health conditions including diabetes, cardiovascular diseases, obesity, and chronic lung conditions, experience more severe and longer lasting symptoms and side effects, and are more likely to die than those who are healthy.
• Those with poor nutritional status are more likely to be immuno-compromised and susceptible to infection, and are likely to have worse outcomes.
• Severe COVID-19 infections usually involve the overproduction of proinflammatory cytokines which can lead to multi-organ failure, and eventually death (1,2).

The Role of Supplements

 Here are some reasons why you may want to supplement your healthy diet with vitamins, minerals and nutraceuticals:

•  The immune system cannot function efficiently without an adequate intake of vitamins, minerals and trace elements.
• Nutrient deficiencies suppress immune functions and increase susceptibility to infections, with increased risk of serious illness or death.
• Infections aggravate micronutrient deficiencies by reducing nutrient intake, increasing losses, and interfering with utilization of nutrients by altering metabolic pathways.
• Anti-inflammatory nutrients are of particular importance due to the damage done by the cytokine storm seen in severe COVID-19 infections.
• Nutritional supplements are widely available, have a long history of safe use and have negligible side effects if taken in tried and tested doses.

For these reasons vitamins, minerals, probiotics, and nutraceuticals are being considered as a safe and effective way of reducing the risk of Sars-CoV-2 infection and reducing the symptoms of COVID-19 including systemic inflammation and endothelial damage (3,4). 

 Here we will look at which supplements can support your immune system and reduce your risk of becoming seriously ill.

 B vitamins

The B vitamins are actively involved in the healthy functioning of the immune system (5) and are specifically required for cytotoxic cellular immunity and to modulate T cell responses (6).

Vitamin C

 Studies indicate that vitamin C may both prevent and alleviate infections caused by bacteria and viruses.  Vitamin C is a powerful antioxidant that scavenges free radicals as well as restoring other antioxidants. It may reduce virally induced damage, prevent viral replication and down-regulate inflammation. In addition patients with acute viral infections have low circulating vitamin C levels, as vitamin C is used up more quickly during illness (7,8,9). Higher doses than usual are needed to have an impact on viruses with 6-8 g per day being shown to be effective. It should be noted that high doses of vitamin C can cause loose bowels.

 Vitamin D

 Vitamin D deficiency is correlated with a higher susceptibility to infections. Vitamin D plays an important role in our immune response and supports an anti-inflammatory cytokine profile (9,10).

 Zinc

 When zinc deficiency was identified in the 1960s it quickly became clear that zinc is vital for a healthy immune system. Zinc has anti-inflammatory and antioxidant properties. Zinc is important for the maintenance and development of both the innate and adaptive immune system (6,11).  Zinc deficiency reduces our defences against infection and increases the risk of inflammation (12). Zinc has also shown specific immune-modulatory effects in viral respiratory infections (13).

 Omega 3

The essential fats are vital for many aspects of health. Omega 3 fats have an anti-inflammatory effect and are actively involved in the proper functioning and strengthening of the human immune system against viral infections (5).

Curcumin

Supplementing with curcumin, derived from turmeric, has been shown to support the immune system and reduce inflammation (14,15). Recent research has shown that a combination of vitamin C, curcumin and glycyrrhizic acid (from liquorice) may be helpful in regulating the immune response to combat CoV infections and in inhibiting excessive inflammatory responses potentially preventing the onset of a cytokine storm (16).

Probiotics

 Probiotics such as Lactobacillus and Bifidobacterium are being used in the treatment and prevention of many conditions and in promoting human health generally. They have recently been found to decrease the risk and duration of respiratory infections and protect against microbial pathogens, including viruses (17). Probiotics may exert their antiviral effects directly by interacting with the virus or by stimulating the immune system to fight them (18). Interestingly, some patients with COVID-19 have been found to have decreased beneficial bacteria such as Lactobacillus and Bifidobacterium (19).

 Protein

Protein is important for repair and maintenance of body tissue, hormones, enzymes, antibodies and for a healthy immune system. Good sources of protein include meat, fish, eggs, nuts, seeds, pulses, tofu and tempeh. Protein powders and protein bars can be useful additions to the diet especially at times when extra support is needed.

References

 The Lancet. Resp Med. Vol 8, Issue 6, e46-e47, June 01, 2020 COVID-19 cytokine storm: the interplay between inflammation and coagulation. Jose RJ, Mauel A.

1. Nutrients 2020 May 19;12(5):1466. COVID-19: The Inflammation Link and the Role of Nutrition in Potential Mitigation. Zabetakis I.

2. Nutrients 2020 Apr 23;12(4):1181. Optimal Nutritional Status for a Well-Functioning Immune System Is an Important Factor to Protect against Viral Infections. Calder P et al.

3. Nutrients 2020 Jun 8;12(6):1718. Diet Supplementation, Probiotics, and Nutraceuticals in SARS-CoV-2 Infection: A Scoping Review. Infusino F et al.

4. Arch Physiol Biochem . 2020 Jul 9;1-10. Nutrients in prevention, treatment, and management of viral infections; special focus on Coronavirus. Bourbour F et al.

5. Endocr Metab Immune Disord Drug Targets 2019;19(8):1100-1115. The Role of the Status of Selected Micronutrients in Shaping the Immune Function. Elmadafa I et al.

6. Biancatelli C et al. The antiviral properties of vitamin C. Expert Rev Anti Infect Ther. 2020 Feb;18(2):99-101

7. Hemila H. Vitamin C and Infections. Nutrients. 2017 Mar 29;9(4). pii: E339

8. Ann Nutr Metab 2007;51(4):301-23. Contribution of selected vitamins and trace elements to immune function. Wintergerst ES et al.

9. Eur Rev Med Pharmacol Sci. 2020 Aug;24(15):8187-8193. Inhibitory effects of Vitamin D on inflammation and IL-6 release. A further support for COVID-19 management? Orru B et al.

10. Maares M et al. Zinc and immunity: An essential interrelation. Arch Biochem Biophys. 2016 Dec 1;611:58-65.

11. Wessels I et al. Zinc as a Gatekeeper of Immune Function. Nutrients. 2017 Nov 25;9(12). pii: E1286.

12. Diabetes Metab Syndr Jul-Aug 2020;14(4):367-382. Enhancing immunity in viral infections, with special emphasis on COVID-19: A review. Jayawardena R et al.

13. Foods. 2017 Oct 22;6(10). pii: E92. Curcumin: A Review of Its' Effects on Human Health. Hewlings SJ, Kalman DS.

14. Crit Rev Food Sci Nutr. 2019 Jan 11:1-53. Cellular and molecular mechanisms of curcumin in prevention and treatment of disease. Patel SS et al.

15. Nutrients 2020 Apr 24;12(4):1193. A Novel Combination of Vitamin C, Curcumin and Glycyrrhizic Acid Potentially Regulates Immune and Inflammatory Response Associated with Coronavirus Infections: A Perspective from System Biology Analysis. Chen L et al.

16. Abdelhamid AG et al. Probiotic Lactobacillus and Bifidobacterium strains possess safety characteristics, antiviral activities and host adherence factors revealed by genome mining. EPMA J. 2019 Sep 5;10(4):337-350

17. Lehtoranta L et al. Nutrients. 2017 Mar 29;9(4). pii: E339. Eur J Clin Microb Infect Dis. 2014 Aug;33(8):1289-302.

18. Xu K et al. Management of corona virus disease-19 (COVID-19): the Zhejiang experience. Zhejiang D Xue Xue Bao Yi Xue Ban. 2020 Feb 21;49(1):0.