30 zinc isotopes from the 54–83 mass range were discovered, of which 64Zn, 66Zn, 67Zn, 68Zn and 70Zn areotopes are stable.
It was discovered in India or China before 1500 BC Knowledge of this metal only came to Europe in the 17th century.
Zinc is one of the necessary microelements – this fact was only confirmed in 1957. It is present in active centers of many (about 200) enzymes participating in various processes, including metabolic transformations. In addition, many transcription factors, regulatory proteins, and other types of DNA binding proteins contain so-called zinc fingers. Therefore, zinc affects all basic life processes. It participates, among others, in bone mineralization, wound healing, affects the work of the immune system, the proper secretion of insulin by the pancreas and the concentration of vitamin A and cholesterol. It contributes to the regulation of blood pressure and heart rhythm. It is also necessary for the synthesis of compounds that regulate plant growth and development. Zinc increases sperm production.
Its minimum daily intake is 5 mg, recommended 15-20 mg. Absorption from the gastrointestinal tract is 10-40% and occurs mainly in the small intestine. Absorption from food is hormone regulated and depends on demand (increases in deficiency states). Animal proteins and citric acid facilitate the absorption of zinc, while iron and copper impede it.
Zinc deficiency causes anemia, growth retardation, birth defects, poor wound healing, psoriasis-like skin changes, dermatitis and hair loss, poor glucose tolerance, diarrhea, and loss of appetite. Adults may also experience: dust blindness, decreased immunity, thymus and lymph node disorders, taste and smell disorders (it is estimated that about 25% of symptoms of taste and smell disorders are caused by zinc deficiency). It can promote atherosclerosis because it reduces the cell’s resistance to damage. In children, a deficiency of zinc means that they are lower than their peers and develop worse mentally.
Some studies indicate that the administration of zinc may reduce the severity of symptoms in children with ADHD who have deficiencies of this element. However, the role of zinc supplementation in this disease is not confirmed and requires further research.
An element deficiency in plants causes chlorosis and leaf dwarfing.
Zinc has healing effects on stomach ulcers, persistent varicose veins, rheumatism, ulcers, acne, skin diseases.
Zinc (II) salts are carcinogenic in large quantities.
Regular use of some pharmaceuticals, including birth control pills, and drinking alcohol reduces the level of zinc in the human body.