Nutrients for the Immune System

March 19th, 2021 | Posted in Info

If you’ve read the blog posts Protection from Covid-19 and Diet, the Immune System and Covid-19 you’ll understand the importance of being in a good state of health and having a robust immune system when it comes to not succumbing to severe infections.

Here we’ll look at how supplementation with individual or multiple nutrients may modulate the severity of Covid-19 in individuals and suggest that dietary and supplement guidelines for at risk populations at a global level may help to modulate the trajectory of the Covid-19 pandemic globally as well as improving the effectiveness of the vaccines.

Here’s why you want to avoid being deficient in any nutrient:

  • The immune system cannot function efficiently without an adequate intake of vitamins, minerals and trace elements.
  • Nutrient deficiencies suppress immune function and increase susceptibility to infections, with increased risk of serious illness or death.
  • Immune cells require a lot of energy to perform their regular functions but when cells are infected, their nutritional requirements increase dramatically in order to activate the immune response.
  • Infections aggravate micronutrient deficiencies by reducing nutrient intake, increasing losses and interfering with utilisation of nutrients by altering metabolic pathways.
  • Vitamins, minerals and trace elements modulate the immune response and impede viral infections.
  • 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.

The Case for Supplements

The European Food Safety Authority has authorised health claims for vitamins A, B6, folate, B12, C and D, and the minerals zinc, selenium, iron and copper for their contributions to the normal functioning of the immune system (1). These micronutrients play key roles in reducing the risk of infections.

Given that we know that nutrient deficiencies may lead to complex and serious health complications supplementation with vitamins and minerals could play a central role in supporting immunity and preventing infections, particularly in those who are at risk of nutrient deficiencies.

Nutrition and Vaccine Response

An effective immune response to a vaccine requires the host to have an adequate nutritional status. Many people, particularly older people, are deficient in key nutrients needed for immune function.  Randomised controlled trials demonstrate a cause-and-effect relationship between micronutrient status and vaccination response. Such trials in older people have shown better responses to vaccination after nutritional intervention (1). Researchers propose that a nutritional supplement containing immune supportive nutrients should be provided free of charge to all those aged over 70 years for a few weeks before and after they receive the vaccine.

Nutrient Deficiencies Are on the Rise

In the UK the 2019 National Diet and Nutrition Survey showed ‘a sustained worsening of dietary intakes and chronic shortages of several of the nutrients involved in supporting the normal immune functions’; these included vitamins A, B12, C and D and the trace minerals zinc, selenium and copper (1). Such micronutrient deficiencies may limit the effectiveness of the Covid-19 vaccines as well as increasing the risk of suffering worse outcomes from infection.

Protect Yourself

For these reasons vitamins, minerals, probiotics, and nutraceuticals are being considered as a safe and effective way of reducing the risk and effects of Covid-19 including systemic inflammation and endothelial damage (2,3).  Indeed, some countries are already using vitamins A, B12, C,  D, zinc, iron and magnesium in the treatment of coronavirus patients. The UK government currently recommends people take vitamin D through the autumn and winter. If you want to protect yourself further you may want to consider whether you are suffering from deficiencies in any of the following nutrients, and to supplement if you think you may be lacking:

  • Vitamin A
  • B vitamins
  • Vitamin C
  • Vitamin D3 with K2
  • Vitamin E
  • Iron – check with your doctor before supplementing with iron
  • Magnesium
  • Selenium
  • Zinc
  • Omega 3 fats
  • Probiotics


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

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

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.

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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.

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

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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

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Heliyon online 12th Feb 2021. Prospects of Nutritional Interventions in the Care of COVID-19 Patients. Alam S et al

1. Rayman M, Calder P. Optimising COVID-19 vaccine efficacy by ensuring nutritional adequacy. Online: Cambridge University Press: 28 January 2021