It strengthens cell walls, participates in enzyme synthesis, and supports the proper functioning of the body in several different ways. Zinc may be a trace element, but its role in the body is hard to overestimate. Let’s take a look at how it supports our body’s response to diseases!
Contents
Mechanism of zinc action in the immune system
Zinc plays a significant role in the proper functioning of the immune system, as it affects the development and activity of key immune cells. It is essential, among others, for T lymphocytes, which coordinate the immune response and help the body recognize pathogens, as well as for B lymphocytes responsible for antibody production. Zinc deficiency can lead to disorders in their maturation and weakening of the immune reaction.
This element also participates in the regulation of cytokine production – signaling proteins that enable communication between immune system cells and control the course of inflammation. Thanks to this, zinc helps maintain a balance between effective defense against microorganisms and an excessive inflammatory reaction; zinc limits fever to the necessary level required to slow down viruses and increase the effectiveness of white blood cells, and at the same time ensures that T lymphocytes recognize the pathogen and B lymphocytes produce the correct antibodies.
Zinc and infections
In the context of viral infections, especially the common cold, zinc is one of the most thoroughly studied trace elements. Numerous randomized clinical trials and meta-analyses suggest that when zinc supplementation is started within the first 24 hours of symptom onset, it can shorten their duration by an average of about 1-2 days compared to placebo in adults1. In one study, patients who took zinc lozenges ended their infection after an average of 4.5 days, while in the placebo group, bothersome symptoms lasted over 8 days2.
The mechanisms of zinc action during infection are multifaceted. Zinc ions can directly interact with viruses – for example, bind to the surface receptors of rhinoviruses, which most often cause colds, and limit their ability to attach to host cells. Furthermore, zinc affects the host’s immune response: it helps maintain the integrity of the respiratory epithelium, which constitutes the first barrier against pathogens, and modulates the functions of immune cells and signaling molecules – which can support virus elimination and reduce excessive inflammation3.
Zinc as prevention
As for prevention, the evidence is weaker and less conclusive. Systematic reviews indicate that chronic zinc intake is unlikely to significantly reduce the incidence of the common cold, although some studies have reported a reduction in the number of days with symptoms or a lower number of certain infections in specific groups 4. Generally speaking, zinc does not act as a “blockade” against infection – it does not directly prevent contact between the virus and the body – but by supporting immune barrier functions and immunomodulatory effects, it promotes a more effective response to pathogens.
Despite promising research results, it is worth remembering that the effect of zinc on infections is moderate and may depend on many factors – including its chemical form (organic forms such as zinc picolinate, gluconate, etc., are more absorbable than inorganic forms such as zinc oxide5), dosage, and the timing of supplementation. Additionally, due to the heterogeneity of studies, researchers emphasize the need for further large, well-designed studies to fully determine the optimal conditions for using zinc in the prevention and treatment of viral infections.
Who should take zinc for immunity?
The daily zinc requirement for a healthy person usually does not exceed 13 mg/day, so prophylactic doses to strengthen immunity should at least slightly exceed this value – as is the case, for example, with the BestProtect supplement, containing 15 mg of zinc in two easily absorbable organic forms. Supplementation may be considered primarily by individuals who have an increased risk of its deficiency or a greater need for this element. This applies, among others, to:
- older people, in whom mineral absorption may worsen with age, and natural weakening of immune system function may occur.
- people on elimination diets, including poorly balanced meat-free and entirely plant-based diets, as the bioavailability of zinc from plant products can be limited,
- people with habits that reduce zinc absorption, e.g., smokers and those consuming large amounts of alcohol.
Support in the form of zinc may also be considered by people who frequently get sick ‘without reason’ or experience infections, and are exposed to prolonged stress, which can affect the functioning of the immune system. It is worth emphasizing that supplementation should not replace a balanced diet, and the decision to introduce it should take into account the body’s individual needs and – if possible – be consulted with a specialist.
Bibliography:
- D. Hulisz, Efficacy of Zinc Against Common Cold Viruses: An Overview, Journal of the American Pharmacists Association, no. 44/2004, issue 5.
- AS Prasad, JT Fitzgerald, B.Bao et al., Duration of symptoms and plasma cytokine levels in patients with the common cold treated with zinc acetate. A randomized, double-blind, placebo-controlled trial, Annals of internal medicine, no.133/2000 issue 4.
- M. Science, J. Johnstone, DE. Roth, Zinc for the treatment of the common cold: a systematic review and meta-analysis of randomized controlled trials, Canadian Medical Association journal, no. 184/2012, issue 10.
- D. Nault, TA .Machingo, AG. Shipper et al., Zinc for prevention and treatment of the common cold, Cochrane Database Systematic Review, 2024.
- Wegmuller R., Tay F., Zeder C., Brnic M., Hurrell R.F. Zinc absorption by young adults from supplemental zinc citrate is comparable with that from zinc gluconate and higher than from zinc oxide Journal of Nutrition, no. 144/2014, issue 2;
- Szcześniak M., Grimling B., Meler J., Zinc – the element of health, Farmacja Polska, vol. 70, no. 7/2014.
- M. Jarosz, E.Rychlik et al., Nutritional standards for the population in Poland and their application, National Institute of Public Health, 2020.