Ten evidence-based nutrients that have been shown to support viral immunity


Zinc (Zn) is an essential micronutrient known to play a central role in the immune system, involving multiple mechanisms, from skin membrane barrier integrity, to the regulation of lymphocytes, it is critical in generating both innate and acquired (humoral) antiviral responses.

Zinc is required for normal development and function of neutrophils and natural killer cells.

Zinc deficiency also affects the activation potential of T lymphocytes, Th1 cytokine production, and B lymphocyte assistance (e.g. via antibody production).

Macrophages are pivotal to all cellular immunologic functions; however, these functions are adversely affected by zinc deficiency, subsequently dysregulating intracellular infection control, cytokine production, and phagocytosis.

Zinc also provides general metabolic antioxidant support and can stabilize membranes.

Zinc, being an integral component of many viral enzymes, proteases, and polymerases, supports the optimum resilience of function of cells – highlighting the importance of regulating cellular and systemic zinc distribution to inhibit viral replication and distribution.



Selenium (Se) is an essential trace element having biological functions of utmost importance for human health.

Most Seleno-proteins participate in antioxidant defence and as a cofactor in redox regulation, particularly via the various types of glutathione peroxidases (GPxs).

Glutathione is an intracellular reducing agent that helps maintain the redox potential of the cell and is important for both extra- and intra-cellular immune function & has been shown to block replication of HIV, HSV-1, influenza virus, and potentially other viruses.



N-acetylcysteine (NAC) is the key rate-limiting precursor amino acid in the production of Glutathione (supported by Selenium as a cofactor).

NAC has demonstrated antioxidant, anti-inflammatory and mucolytic activity, as well as being an effective enhancer of T-cell function.

Studies have shown that NAC is able to reduce the duration of intensive care unit (ICU) stays during conditions involving respiratory distress.



Vitamin A is critical to a competent immune system. Vitamin A rich foods have been utilised to maximise immunity during cold and flu season throughout the world for centuries.

Vitamin A assists numerous defence mechanisms via direct genetic and receptor-based interactions (when balanced in tandem with Vitamin D) for increasing infection resistance.

Vitamin A activates B & T lymphocytes, acts as a lipid antioxidant, enhances antibody production and phagocytosis, as well as supporting healthy membrane function and integrity.

The natural forms of Vitamin A found in Arctic Cod Liver oil may provide one of the safest and most effective ways of delivering this important nutrient to the body.



Almost all cells in the body have Vitamin D Receptors (VDRs) due to the importance of its hormone-like structure for mediating the proper functioning of the cell (via direct gene expression regulation).

Resting T and B lymphocytes do not have a VDR, but when activated, their expression of VDR is induced, demonstrating the importance of sufficient vitamin D for regulating immune functions during the active stages of infection and inflammation.

Vitamin D influences the action of Dendritic cells (which are particularly important for immunosurveillance), as well as regulating the production of several cytokines including IL-2, TGFB1 and immunoglobin synthesis in activated B cells.

This capacity for Vitamin D to act as a potent immunomodulator may be especially important during the active stages of an immune response to infection (since phenomena like Cytokine storms are a significant cause of tissue damage during pronounced infective disease).

(16,17,18, 20,21)


Increasing the Lysine / Arginine ratio of available amino acids in tissues has been shown to potentially inhibit the stability and replication of various viruses including Herpes, Influenza A, and other viruses.

Lysine is an amino acid found in one of the highest quantities in quality dietary protein sources, making large amounts potentially necessary to the body at certain times, and generally well tolerated by the body.

Lysine also has a key role in the integrity of collagen and connective tissues important for maintaining healthy tissue membranes.



(Ascorbic acid)

Ascorbic acid is water-soluble, and acts as a chain breaking antioxidant, reacting directly with singlet oxygen, hydroxyl radicals, and superoxide radicals.

As an electron donor, vitamin C’s direct antioxidant effects protect cells from endogenous and exogenous reactive oxygen and nitrogen species.

Vitamin C is also involved in the regeneration of other antioxidants, such as vitamin E and glutathione, back to their active state.

Vitamin C has antiviral activity which may be due, at least in part, to enhanced interferon activity.





The high concentration of branched galactose structures in arabinogalactan fibre (from Larch tree) has been shown to provide an ideal soluble prebiotic fibre to the digestive tract (providing anti-inflammatory support benefits via its positive influences on the gut membrane and microbiome).

In cell and animal models, Arabinogalactan is capable of enhancing the function of macrophages, natural killer cells, and pro-inflammatory cytokines, increasing the human body’s potential to defend against cold virus infections.

Furthermore, of particular note is the potential for these structures to bind directly to certain viruses, possibly inhibiting their ability to attach to cells in the first place (although this potential has not been studied for all novel and specific viruses so far).

Around 200 volunteers who had experienced at least 3 Respiratory Infections within the past 6 months were trialled on 4.5g Arabinogalactan vs a Placebo. Arabinogalactan significantly increased the participant’s capacity to defend against infections, resulting in a reduced incidence and/or severity of common cold virus infections in the treatment group.

Notably, some studies have also shown a significant increase in the percentage of CD8+ T-suppressor cells, and the proportion and proliferation of monocytes in lymphocyte populations. This suggests Arabinogalactan can influence TNF-a secretion, and modulate immune cell proportions.

This is significant because it demonstrates not only an ability to potentially increase immunity and resilience to infection, but also more crucially to support the regulation of the inflammatory response during infection (to assist symptoms and tissue damage remaining under control).




The abrupt elevation in inflammatory mediators during viral infection, may reach excessive levels in certain individuals and situations (e.g. Cytokine storm), making the initially protective immune response particularly damaging to the body if it progresses beyond a manageable level.

Having safe mechanisms for downregulating an overactive immune response may therefore be beneficial to have in such instances.

Curcumin has been shown to have potent anti-inflammatory capabilities (without the same degree of immunosuppression seen with NSAIDs and Corticosteroids), when taken at typical therapeutic doses, and may therefore provide a helpful complementary support during severe infection stages.

Curcumin has also demonstrated direct inhibitory effects on various bacteria, fungi and viruses, namely HBV, HCV and HIV – with differing mechanisms of action proposed for each, however a ‘degradation by default’ pathway is thought to be a commonality contributing this effect.




Palmitoylethanolamide (PEA), typically being used for neurogenic pain, also has notable anti-inflammatory benefits (including within the nervous system).

Many viruses are known to infiltrate the nervous system as a conduit to the rest of the body, and therefore potentially act as a haven for dormancy (for possible later resurgence).

As a result, the active stages of an infection can cause numerous nervous system symptoms, including considerable neurogenic pain (e.g.  shingles).

PEA may provide a dual benefit of not only calming inflammation and limiting damage to delicate nervous system tissues, but may also help minimise pain perception during the inflammatory stages of such viruses.



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