Zinc – An Essential Life Link

Zinc, a metal available abundantly in nature with extensive industrial applications is, interestingly, an essential trace element with established biological functions in the human body (Prasad, 1995). 

The biological role of zinc runs deep into realms of the genes through the cellular growth, maintenance, and functions. Hence, zinc deficiency leads to various serious health complications.

Oysters, red meat, poultry, beans, nuts, whole grains, cereals, and dairy products are good sources of zinc (https://fdc.nal.usda.gov/). Since, Phytic acid present in legumes and whole grains reduces the cellular absorption of zinc by binding to them, soaking them in water for several hours before cooking or sprouting them before consumption is highly beneficial (Sandstrom, 1997). 

The Recommended Dietary Allowances (RDAs) for zinc differs between gender and age groups as per the data published by the Institute of Medicine, Food and Nutrition Board, Washington, DC (https://www.nap.edu/). 

Numerous Zinc supplements containing zinc in the form of zinc gluconate, zinc sulfate, and zinc acetate with varying percentage of elemental zinc are available OTC.



Zinc - the Crucial Cell Constituent

Zinc plays a key role in the construction and conservation of the genetic components of the cell. The human cells will never multiply or grow, but for zinc. The skin, connective tissues, teeth, bones, nails, and hair, all need zinc in trace amounts.

Numerous physiological events like sugar metabolism, enzymatic catalysis (Sandstead, 1994), protein breakdown, fat hydrolysis, calcium absorption and hormonal balance, all depend on zinc.  

Insulin production, and pancreatic cell maintenance just shall fail; thyroid, adrenal glands, ovaries, and testes will malfunction and there will be not enough sex hormones if there is no sufficient zinc. Abnormal weight loss, loss of appetite, amenorrhea in women, impotence in men, depression, poor wound healing, and skin manifestations are a few other indicators of zinc deficiency (Maret and Sandstead, 2006).  

An abnormal embryo with poorly developed neurons (Simmer and Thompson, 1985) and sensory organs is yet another risk of zinc deficiency (Heyneman,1996). There would be scanty milk available for the newborn from zinc deficient mothers (Caulfield et al, 1998).

Zinc -The Immune Booster 

Zinc sufficiency enhances the innate immunity since the production of vital components of the immune system, including antibodies, and white blood cells largely depend upon zinc (Rink and Gabriel, 2000). Studies have found that zinc supplementation potentially reduces the duration of the common cold (Wang et al, 2020). 

A recent retrospective observational study in the NYU Langone Health Hospitals in New York has shown that zinc sulphate supplementation plays a role in therapeutic management of COVID-19 infection (Carlucci et al, 2020). 

More recent studies have also demonstrated inhibition of viral replication by zinc in some rhinoviruses, HCV, and the influenza virus, suggesting that zinc supplementation could be effective for the prophylaxis and treatment of COVID-19 infection as well (Kumar et al, 2020). 

Zinc- The Darling of the Psychiatrists

It is fascinating to note that zinc is an essential mineral for normal brain functions such as glutamate mediated neurotransmission involving glutamate dehydrogenase, a metalloenzyme that contains zinc. Thus, therapeutic zinc supplementation helps in the alleviation of symptoms involving glutametergic transmission, adrenal hypertrophy, and higher levels of corticosteroids (Humphries et al, 1989). 

Clinical studies on patients afflicted with Anorexia nervosa, a psychiatric eating disorder have shown that therapeutic zinc supplementation can compensate for the (Casper et al. 1980) reduced intake and absorption of dietary zinc in the cohort. Studies have also elucidated a restoration in leptin levels during therapeutic zinc supplementation (Mangian et al, 1998).

Zinc – The Modern ‘Manna’

Research studies have shown that zinc prevents the progression of age-related macular degeneration (AMD) and vision loss, delaying the cellular damage to the retina (Evans, 2006). Zinc has also been shown to help retention of the skin integrity and mucosal membranes (Wintergerst et al, 2007). Zinc is perhaps a perhaps the modern ‘Manna’ that helps you stay young, free from diseases and ageing (Fabris and Mocchegiani, 1995).

Conclusion

Though zinc is a vital life component, zinc supplements potentially interact with certain therapeutic drugs such as quinolone antibiotics and tetracycline, and diuretics like thiazide. Acute high zinc intake could be deleterious too with nausea, vomiting, loss of appetite, abdominal cramps, diarrhea, and headaches. Chronic high intake may lead to copper deficiency, distorted iron function, and reduced levels of high-density lipoproteins. Hence, it is good to take the recommendations of a health care provider to decide upon the correct dose of zinc.

This article was written by Professor B.V. Ramanan

This is not intended to treat or diagnose any illness or disease. If you have any questions about your health please consult you doctor



Reference

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