Zinc is an essential microelement of the human body, what is the harm of zinc deficiency, and what is the impact of excessive zinc supplementation on the body?

Zinc is an essential trace element that is involved in almost all metabolic processes in the human body. Zinc deficiency or insufficiency can lead to growth retardation, decreased immune function and abnormal neuropsychological development in children.

ZincHistorical Development of the Element

Zinc was identified as an essential element in plant nutrition in 1869. In 1934, it was proven that zinc is an essential element for animals. As for zinc deficiency in humans, it was not until the 1960s, when Prasad et al. conducted extensive research, that the first evidence was presented that dwarfism in humans was a zinc deficiency disease, and in the 1970s, when Moynahan demonstrated that enteric limb dermatitis was a hereditary disorder of zinc metabolism.

Metabolism and physiological function of zinc

Zinc is widely distributed in different tissues and organs in the human body. Zinc is absorbed in the small intestine by active transport, and both dietary zinc intake and intestinal zinc excretion regulate the balance of zinc metabolism in the body.

What are the symptoms of zinc deficiency

Current research shows that zinc deficiency is widespread among the population, especially in economically disadvantaged developing countries, and that those in poorer economic conditions are the most at risk. Among the different population groups, infants, children, pregnant women and women of childbearing age have the highest prevalence of zinc deficiency. Zinc deficiency is often accompanied by the presence of iron deficiency.

Mild zinc deficiency

Mostly occurs in people with short-term insufficient zinc intake, and signs and symptoms are often atypical, making recognition difficult.

Moderate zinc deficiency

Mostly seen in people with chronic inadequate zinc intake or diarrhea, the main manifestations can be seen in diarrhea, growth retardation, anorexia, delayed sexual maturation, behavioral changes and other manifestations.

Severe zinc deficiency

Rarely, it occurs in children with enteropathic dermatitis of the extremities or long-term use of penicillamine to treat hepatomegaly (WD). The triad of oral and periprosthetic dermatitis, diarrhea, and alopecia areata is the characteristic presentation.

The clinical manifestations of zinc deficiency vary in children and adolescents of different ages.

Zinc deficiency prevention

Zinc in the human body is mainly obtained through diet.

To prevent zinc deficiency, first of all, we need to adhere to a balanced diet, animal food and plant food, avoiding partiality, eat some zinc-rich red meat (beef, lean pork, liver, etc.), part of the seafood (such as oysters, but should not be eaten in large quantities), fish, poultry and so on.

The daily supply of zinc should be supplemented for those who are at high risk of zinc deficiency, such as preterm infants/children with low birth mass, patients with chronic diarrhea and malabsorption syndrome, and patients with long-term parenteral nutrition.

0-6 months old babies, advocate breastfeeding, can not breastfeeding, choose to fortify zinc formula.

After 4-6 months of age, it is recommended to prefer zinc-fortified baby food or zinc-rich animal foods such as meat and liver.

Diarrhea, zinc supplementation is given orally to children with diarrhea during active oral rehydration salts therapy. Supplementary dose: under 6 months 10mg/day; 7 - years 20mg/day for 10-14 days

Treatment of zinc deficiency

When there is a zinc deficiency, the first step is to actively remove and correct the cause of zinc deficiency. Zinc supplementation should give priority to daily dietary zinc supplementation.

Normal breastfeeding is usually sufficient to correct zinc deficiency in preterm infants. Breast milk may be deficient in zinc if maternal zinc reserves are excessively depleted or zinc is deficient.

The recommended daily intake of dietary zinc for breastfeeding adult women has been increased from 11 mg per day to 12 mg per day. if milk production is low, the infant will need supplemental replacement.

Zinc supplementation therapy should be administered orally, and zinc supplements that are soluble in water, easily absorbed, have a better taste, and are less costly are preferred.

Risks of excessive zinc supplementation

When daily dietary zinc is adequate, the addition of zinc supplementation medication carries the risk of exceeding the UL dose of zinc intake. The safety profile of zinc supplementation is good up to the maximum intake tolerance (UL)

Adverse effects are rare in pediatrics, but high doses of zinc can be acutely toxic and may adversely affect the immune system, iron, copper, and cholesterol status, and can result in nausea, vomiting, decreased appetite, diarrhea, and headache, anemia, neurological lesions, and lipid metabolism abnormalities.