A recent article published in Advances in Nutrition discussed that zinc is an essential trace element that is crucial for growth, development and maintenance of the immune function. This micronutrient influences all organs and cell types, representing an integral component of approximately 10% of the human proteome and encompassing hundreds of key enzymes and transcription factors.

However, zinc deficiency is common, affecting up to a quarter of the population in the developing nations, but also affecting distinct populations in the developed world—as a result of lifestyle, age and disease-mediated factors. Therefore, zinc status is a critical factor that can influence antiviral immunity, especially, as zinc-deficient populations are often most at risk of acquiring viral infections such as HIV or hepatitis C.

The authors stated that evidence of over the past 50 years demonstrate the antiviral activity of zinc against a variety of viruses and via numerous mechanisms. The therapeutic use of this trace element for viral infections, such as herpes simplex and the common cold, has stemmed from these findings.

The tight regulation of zinc homeostasis both systemically and intracellularly indicates that zinc plays an essential role in human health. Although zinc is a component of ∼10% of the human proteome, zinc in different forms (free compared with protein-bound) can stimulate a variety of signaling events, including the antiviral response – rendering a direct antiviral, as well as a stimulant of antiviral immunity. The article reported that in vitro studies have suggested that free zinc may possess potent antiviral effects, and this evidence is supported by trials of creams, lozenges, and supplements with high free zinc content.

Scientists postulate that zinc-binding proteins, such as the metallothioneins, may possess antiviral roles. Zinc treatment applied at a therapeutic dose and in the right form has the potential to drastically improve the clearance of both chronic and acute viral infections, as well as their accompanying pathologies and symptoms. The role of zinc as an antiviral can be categorized as – zinc supplementation implemented to improve the antiviral response and systemic immunity in patients with zinc deficiency and zinc treatment performed to specifically inhibit viral replication or infection-related symptoms.

Source: Advances in Nutrition. 2019 Jul 1;10(4):696-710. doi: 10.1093/advances/nmz013.