As we arm ourselves for our battle with COVID-19, we must not forget zinc.  This is especially true for those over the age of 40, and the need increases with increasing age. According to the US Department of Agriculture, 73% of Americans are deficient in zinc, and deficiency is especially found in older people—even those who report taking zinc supplements. 

Zinc is one of the foundation nutrients needed for building a strong immune system. Even a small deficiency can significantly impair immune function. Research over the past twenty years has shown that having adequate zinc reserves in cells inhibits replication of the coronavirus family of viruses, of which COVID-19 is a member. If a virus can’t replicate (reproduce itself), it can quickly and easily be eradicated by the immune system. 

Zinc has also been shown to restore vigor to immune cells and to reduce excess inflammation. Controlling excess inflammation is extremely important in COVID-19 infections because it is excess inflammation in the lungs—the so-called “cytokine storm”— that causes death in severe cases.

Meanwhile, chronic inflammation is a constant tax on the immune system, weakening immunity, and it tends to increase with age. This chronic inflammation is part of a phenomenon that has been coined “immunosenescence,” and was described in an article in the Journal of Nutritional Biochemistryas “progressive dysregulation of immune responses observed in older adults that results in increased susceptibility to infectious diseases, impaired vaccination efficacy and systemic low-grade chronic inflammation.”

Is zinc deficiency the cause of immunosenescence? It certainly appears to be a major factor, and it’s been shown that zinc helps to reverse immunosenescence. In a 2007 study, for example, a group of older men and women were given either 45 mg of zinc per day or a placebo for one year. In that year, the supplemented group had a total of 7 infections compared with the placebo group’s 35; and when the zinc-takers got infections, they had milder symptoms. Although most of the study participants were evaluated as being borderline zinc-deficient when the study began, even those who had been in the normal range benefited from supplementation (indicating that what is considered normal is not necessarily optimal).

We recommend that most people supplement with at least 30 mg per day of zinc; for those over forty, at least 50 mg per day. It’s not hard to become deficient in zinc. Zinc isn’t stored well in the body and gets lost in sweat, during stress, and when facing an immune challenge. Also, vegetarian and vegan diets are usually low in zinc.