After iron, zinc is the most abundant trace element in the body (2 to 4 g). 98 % is found in our cells and just 1 % in the plasma. Zinc is an essential trace element that is crucial for growth, development, and the maintenance of immune function.
Zinc, a trace element essential to many physiological roles:
- Zinc is involved in the activity of more than 300 metalloproteins and metalloenzymes where it acts as a metallic cofactor. This means that these specific proteins and enzymes can only function if zinc plays a structural or regulatory role.
- Zinc is essential then to multiple biological reactions (immunity, growth, insulin synthesis, etc.) and plays a major role in the body in all major metabolic processes and physiological mechanisms.
Its influence reaches 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.
ZINC And Immunity:
A cause and effect relationship has been recognized and accepted by EFSA between dietary intake of zinc and normal immune system function. In fact, zinc plays a dominant role in the body’s natural defense, from maintaining the skin barrier to immune cell activity.
Zinc is involved in the function of thymulin, a hormone that stimulates the development and maturation of T lymphocytes in the thymus. These cells play a major role in the immune response, as they recognize and fight against foreign bodies, pathogens, and cells infected with the virus.
In addition, scientific studies have shown numerous mechanisms by which zinc is involved in the viral replication cycle. (Replication is the phenomenon by which the virus, once it has infected a cell, multiplies and produces new viruses, thus spreading the infection to other cells).
The role of zinc in the antiviral response can be summarized in 2 actions, therefore:
- Improvement of the immune response (activation of T lymphocytes)
- Inhibition of viral replication and of multiplication of the virus in the body. THE ANTIVIRAL POTENTIAL OF ZINC IS THE FOCUS OF NUMEROUS STUDIES:
One study in vitro observed that an increase in cellular zinc concentration effectively impairs replication of RNA viruses such as the influenza virus, poliovirus and certain coronaviruses.
A high number of studies have addressed the effect of zinc supplementation on various viral infections. In fact, there would be benefits for the immune response from supplementation in the face of a wide variety of viruses, the best known effects being those observed in therhinovirus which is responsible for colds and respiratory disease.
In the general population, the recommended dietary allowance for zinc varies between 8 mg for women and 11 mg for men. It is also about 11 mg daily for pregnant women. It is still advisable not to exceed a dose of 15 mg zinc per day, from all sources (7 mg for children aged from 10 to 18 years, 3 mg for children aged less than 10 years).
Zinc and Food:
- Zinc is found in many foods such as fish or red meat. Vegan diets are very often deficient in zinc, however.
- To ensure efficient absorption, it is important to avoid combining it with too many cereals or legumes rich in phytates and to avoid consuming too many preserves because preservatives are mineral traps.
- Phytates are actually compounds found in vegetables (maize, rice, cereals, legumes) that bind to certain metals including zinc, and prevent their efficient intestinal absorption.