Journal of Nutritional Disorders & Therapy

Zinc Deficiency: An Overview

Ruth Merry Private University in Los Angeles, California, United States

Received: 15-Dec-2021 Published: 25-Dec-2021

Editorial

Zinc deficiency is described as a lack of zinc to meet the body's needs or a serum zinc level that is below the usual range. Serum zinc is not a good biomarker for zinc status since a drop in serum concentration is only apparent after long-term or severe depletion. Increased diarrhoea is one of the most common symptoms. The skin and gastrointestinal tract, as well as the brain and central nervous system, immunological, skeletal, and reproductive systems, are all affected by zinc deficiency. Reduced dietary intake, insufficient absorption, increased loss, or increased body system utilisation can contribute to zinc insufficiency in humans. Reduced food intake is the most common cause.

In the United States, the Recommended Dietary Allowance (RDA) for women is 8 mg per day and 11 mg per day for men. Oysters, pork, beans, and nuts have the highest zinc content in the diet. An effective preventive measure is to increase the amount of zinc in the soil, and consequently in crops and animals. Up to 2 billion individuals globally may be deficient in zinc. Acne, eczema, xerosis (dry, scaling skin), seborrheic dermatitis, and alopecia are all symptoms of zinc deficiency (thin and sparse hair). It may also make wound healing more difficult or impossible. Oral ulceration, stomatitis, and white tongue coating are all symptoms of zinc deficiency in the mouth. Angular cheilitis is a rare complication (sores at the corners of the mouth). Vision, smell, and taste - A severe zinc shortage can cause problems with smell and taste. Although most cases of night blindness and improper dark adaption in humans with zinc insufficiency have occurred in combination with other dietary deficits, night blindness may be a characteristic of severe zinc shortage (e.g. vitamin A).

Immunological system

People with zinc deficiency can suffer respiratory, gastrointestinal, or other diseases, such as pneumonia, due to impaired immune function. Zinc deficiency affects the levels of inflammatory cytokines in blood plasma, and zinc supplementation causes a dosedependent increase in these cytokines. There is an increased cellular demand for zinc during inflammation, and zinc deficiency leads to poor zinc homeostasis, which is linked to chronic inflammation.

Diarrhea

Zinc deficiency causes diarrhoea to occur more frequently and to be more severe.

Appetite loss

Zinc deficiency might cause you to lose your appetite. Bakan has pushed for the use of zinc in the treatment of anorexia since 1979. Zinc has been demonstrated to improve weight gain in anorexia in at least 15 clinical investigations. Zinc increased the rate of body mass gain in anorexia nervosa patients, according to a 1994 study. Other nutritional deficiencies, such as tyrosine, tryptophan, and thiamine, may also contribute to this "malnutrition-induced malnutrition" phenomena.

Cognitive function and hedonic tone

Zinc deficiency impairs cognitive skills such as learning and hedonic tone. Behavioral disorders such as irritability, tiredness, and sadness are linked to moderate and severe zinc deficiency (e.g., involving anhedonia). In these circumstances, zinc supplementation promotes a rapid and significant improvement in hedonic tone (i.e., general level of happiness or pleasure). Zinc supplementation has been shown to help with ADHD and depressive symptoms. Low plasma zinc levels have been linked to a wide range of psychological problems. Low zinc levels in the brain have been related to schizophrenia. Zinc deficiency may play a role in depression, according to research. Supplementing with zinc may be beneficial in the treatment of serious depression.

Growth

Zinc deficiency in children can cause delayed growth, and it has been stated that one-third of the world's population suffers from stunted growth.

During the course of pregnancy

During pregnancy, zinc deficiency can harm both the mother and the foetus. Maternal zinc insufficiency has been shown in animal studies to disrupt both the sequencing and efficiency of the birth process. In zinc deficient animals, there has been an increased incidence of difficult and prolonged labour, bleeding, uterine dystocia, and placental abruption. The dysfunctional functioning of oestrogen via the oestrogen receptor, which contains a zinc finger protein, may be responsible for these effects. According to an assessment of pregnancy outcomes in women with acrodermatitis enteropathica, one abortion and two malfunctions occurred in every seven pregnancies, implying that the human foetus is equally susceptible to the teratogenic effects of severe zinc deficiency. However, a review of zinc supplementation trials in pregnant women found no evidence of a substantial effect on newborn survival.

When zinc shortage develops throughout infancy and childhood, a period of rapid growth and development when nutritional needs are high, it can disrupt several metabolic processes. Low maternal zinc levels have been linked to decreased attention and motor function throughout the neonatal era. Supplementation has been linked to improved motor development in extremely low birth weight infants and increased robust and functional activity in infants and toddlers in some studies. According to recent study, rising carbon dioxide levels in the atmosphere will increase zinc deficiency in cultures who eat grains and legumes as a primary food.

The edible sections of wheat, rice, peas, and soybeans grown in increased CO2 environments contained less zinc and iron, according to a meta-analysis of data from 143 researches evaluating the nutrient content of grasses and legumes grown in ambient and elevated CO2 habitats. In the late twenty-first century, global CO2 concentrations are predicted to exceed 550 parts per million. The zinc content of these crops was 3.3 to 9.3 percent lower at this CO2 level than that of crops cultivated in the current atmosphere. According to a study of the nutritional impact of reduced zinc levels on the populations of 151 nations, an additional 175 million individuals could be at risk of dietary zinc deficiency as a result of rising CO2 levels in the atmosphere. Because biosystems cannot store zinc, it must be consumed on a regular basis. Zinc deficiency can result from a diet that is too low in zinc, which can be harmful to one's health. The clinical signs of zinc shortage are best understood by understanding that zinc has three functions in the body: catalytic, structural, and regulatory.

Zinc (Zn) is exclusively found in its +2 oxidative form, when it usually takes on a tetrahedral shape. It's crucial for basic biological operations including DNA replication, RNA transcription, cell division, and cell activation to continue. Too much or too little zinc, on the other hand, can damage these functions. Zinc is an essential component of the catalytic sites of hundreds of different metalloenzymes found in humans. Zinc's structural role is to coordinate with specific protein domains, allowing for easier protein folding and the formation of structures like 'zinc fingers.' Zinc is involved in the regulation of nucleoproteins and the activity of numerous inflammatory cells as part of its regulatory role. Zinc, for example, controls the expression of metallothionein, a protein with various roles including intracellular zinc compartmentalization and antioxidant activity. Zinc deficiency disrupts hundreds of metabolic pathways, resulting in a variety of clinical symptoms such as poor growth and development, as well as reproductive and immunological dysfunction.