What is the Importance of Zinc?

Zinc is a necessary micronutrient with over 300 biological roles. Marginal zinc deficiency is common among poor children whose diets are either low in zinc or high in phytates, which inhibit zinc absorption. Infectious disorders, such as diarrhoea and respiratory infections, put these youngsters at a higher risk of morbidity. Under-five children and those exposed to zinc-deficient diets will benefit from either daily zinc supplements for kids or a 10- to 14-day course of zinc treatment for an episode of severe diarrhoea. This includes less severe illness and a lower likelihood of recurring diarrhoea episodes. Given these findings, the World Health Organization/United Nations Children’s Fund now recommends that all children with severe diarrhoea, regardless of aetiology, be treated with zinc. Scientists at ICDDR.B have pioneered the discovery of zinc’s health advantages. The first nationwide scaling up of zinc treatment has now been completed in collaboration with the Ministry of Health and Family Welfare, the Government of Bangladesh, and the business sector. Important obstacles persist in reaching Bangladesh’s poorest people and those living in remote places.

It has been more than a decade since the groundbreaking publications by Sazawal et al. and Roy et al. demonstrating the efficacy of orally administered zinc in the treatment of acute childhood diarrhoea (1,2). Since then, multiple randomized hospital and community-based trials have repeatedly confirmed the efficacy of zinc treatment for acute or chronic diarrhoea in children under the age of five (under-five children) (3-6). Zinc supplements for kids lowers the duration and severity of acute diarrhoea, as well as the chance of a protracted episode, according to pooled analyses of published data (7,8). The findings of these efficacy trials were then repeated in a community-based, effectiveness study of zinc therapy for acute childhood diarrhoea conducted in Matlab’s ICDDR, B rural field site. Children in the zinc intervention group had a shorter length of illness, a lower risk of a repeat bout of diarrhoea, and non-injury mortality in this experiment in which children got daily zinc medication for each episode of diarrhoea. The reduction in mortality was significant (50%). (9). Scientists at ICDDR, B conducted this study as well as several other studies on the effects of zinc on diarrhoea and other ailments, most notably childhood pneumonia.

The World Health Organization (WHO) estimates that the global yearly mortality burden due to zinc deficiency is 750,000 fatalities (10). It is expected that the successful application of zinc as a therapy for infantile diarrhoea will prevent more than half of these deaths (11). Given the possible reduction in mortality and the quality of the evidence in favour of zinc treatment, the World Health Organization (WHO) and the United Nations Children’s Fund (UNICEF) released a joint statement in May 2004 on new guidelines for the management of childhood diarrhoea (12). This includes the advice that all children under the age of five be treated with zinc for 10-14 days (20 mg/day for children aged 6-59 months and 10 mg/day for infants aged less than six months). This advice is currently a policy of the Government of Bangladesh’s Ministry of Health and Family Welfare, with a modest change to cover children as young as two months old.


The lack of a good assessment of zinc supplements for kids status makes population-based estimations of the occurrence of zinc insufficiency in young children difficult. Current estimates are based on one or more zinc-deficiency indicators (s). These include stunting rates, zinc levels in national food sources, blood zinc levels, and dietary intake histories.

Despite the difficulties in precisely determining zinc levels, it is now recognized that mild-to-moderate zinc insufficiency due to insufficient dietary consumption is widespread throughout the world. The higher prevalence of zinc shortage in underdeveloped nations is mostly owing to low zinc intake from animal sources, high dietary phytate concentration (which reduces zinc bioavailability), and insufficient food intake. According to a population-level examination of national food-balance sheets, 21% of the world’s population is at danger of inadequate zinc consumption; however, the percentages are substantially higher in LDCs. These youngsters are especially vulnerable to zinc insufficiency due to low food quality and increased zinc faecal loss due to gastrointestinal illnesses. Children with mild chronic zinc deficiency do not show any clinical indications that would alert professionals to its presence, making it a hidden condition. Bangladesh has one of the highest rates of prevalence in the world, impacting more over half of all under-five children.

Zinc, as a micronutrient component in many metallo-enzymes and poly-ribosomes essential in cellular function, promotes normal growth and development throughout pregnancy, infancy, and adolescence. It is required for metabolic function, cellular development, and immunological function. Despite its critical significance, overt clinical symptoms associated with zinc deficiency are uncommon in humans.

The first published description of clinically-evident zinc deficiency due to nutritional causes in otherwise normal humans occurred in the Middle East in the 1960s among adolescent boys, and was characterized by stunted growth and delayed sexual maturation, both of which were reversible with zinc supplementation. Acrodermatitis enteropathica, a genetic autosomal recessive illness with an inborn metabolic abnormality that leads in impaired intestinal absorption of zinc, is one well-known zinc-deficiency disorder with overt clinical symptoms. The discovery of this hereditary illness and its quick remission when treated with zinc raised clinicians’ awareness of zinc’s potential significance as a clinical deficiency disorder in humans. Not long after this finding, zinc deficiency was discovered in adult patients receiving total parenteral nutrition, which was due to a failure to include zinc in the intravenous infusates. These people had memory loss, skin issues, loss of taste, and an increased susceptibility to infection, all of which went away when zinc was supplied.

Mild-to-moderate zinc deficiency due to insufficient dietary intake is now well-known throughout the world, with a higher prevalence in poorer nations, owing mostly to low intake of zinc from animal sources, high dietary phytate content, and insufficient food consumption.