Zinc is the second most abundant “trace mineral” in the human body, right after iron. Its presence is determined in over 100 different enzymes in the body.

It is a powerful mineral that we need for a healthy immune system, for the proper functioning of thyroid hormones, sex hormones, and to maintain normal blood glucose (insulin) levels. Helps in the metabolism of the breakdown of carbohydrates for energy, but also in maintaining the health of the skin and nails. It also plays an important role in cell division and growth, wound healing, etc.

Zinc in Human Health: Effect of Zinc on Immune Cells

However, perhaps the most well-known positive effect of zinc in the body is its powerful effect in combating colds and other infections that develop, typically, in the cold months of the year. Zinc “fights” with harmful compounds that are constantly formed in the body as a result of various reactions – free radicals.

This antioxidant effect of zinc has a positive effect on overall human health, as well as immunity. Something that is additionally positive. Zinc is often found in plant foods. With that in mind, it is clear that most often when consuming foods rich in zinc, we also consume a range of more antioxidants and other beneficial components, naturally present in fruits, vegetables, and cereals.

Zinc and immunity

The immune system, as the body’s main defense mechanism against various infections and other threats, is of great importance for overall health. Lack of zinc in the body can lead to suppressed function of the immune response. Even a small deficiency can affect macrophages and neutrophils, the natural killer immune cells. The body also needs zinc to make T lymphocytes. Thus, some studies conducted in developing countries indicate that some severe pneumonia and other infections in patients are caused precisely by suppressed immunity as a result of zinc deficiency.

Function in wound healing

Zinc helps maintain the elasticity of the skin and mucous membrane, which is especially important in injuries. It also helps in the production of healthy hair, nails, and healthy skin cells.


Acute diarrhea is among the diseases with the highest mortality in children in developing countries. Dietary zinc deficiency may be one of the main causes of this disease. Zinc plays an important role in the immune response that is reduced in these children, so they are more susceptible to infections such as diarrhea.

Eye diseases

Researchers have suggested that zinc in combination with some antioxidants may reduce the progression of vision loss in the elderly. This action takes place by preventing damage to the retinal cells in the eye.

Flu and different types of colds

Of course, given the effect of zinc on the proper functioning of the immune system and its capacity as a whole, it will indirectly affect the likelihood of developing and complications from the flu and various colds.

Thus, normal levels of zinc in the body are very important. Namely, one study determines a significant, direct impact of zinc in reducing the risk of complications or complete prevention of infections caused by viruses with varying degrees of danger.

Researchers have found that zinc can reduce the risk of severe infection and reduce the duration of symptoms. The mechanism of this action is still at the level of a hypothesis. The hypothesis is that this positive effect of zinc is due to its direct action of inhibiting or preventing the rhinovirus from binding and replicating in nasal tissue.

Several studies determine the positive effect of zinc on flu and colds

A survey was conducted on 50 respondents with flu symptoms. Every 5 hours, half of them took a zinc acetate tablet, while the others took a placebo tablet. Those who took zinc acetate tablets had a significantly reduced period of symptoms (cough, headache, runny nose, and body and muscle pain).

Another clinical study, for respondents had 273 volunteers who were infected with the flu. In the same way, half received zinc gluconate therapy and the other half a placebo tablet. The result was the same: a reduced period of symptoms.

But in both studies, the severity of the symptoms remained the same for the duration.

Many other studies have similar results, but also those that do not show a positive effect. Therefore, further research is needed to determine the exact mechanism by which zinc acts on viral cells and their path in the body.

However, one should be careful, ie keep in mind that the surplus, ie excessive amounts of zinc (usually achieved by supplementation) in the body can cause harm.

Daily recommended intake and foods rich in zinc

The recommended daily intake of zinc for adult men is 11mg, and for women and children is 8mg (12mg for pregnant women).

Healthy foods rich in zinc:

  • legumes
  • nuts
  • whole grains
  • cereals

The phytates that are often present in whole grain foods interfere with the absorption of zinc by binding to it. However, soaking this food in water for a few hours before preparation allows the availability of zinc after preparation.