Type II diabetes is one of the diseases of civilization, the direct cause of which is too high levels of glucose (sugar) in the blood. It is primarily the result of insufficient insulin secretion or improper action of this hormone. Hyperglycemia often causes serious and chronic complications in diabetics, such as kidney disease, eye damage, nervous system disorders (neuropathies) and leads to an increased incidence of cardiovascular disease. Physicians are noting an increased incidence of type II diabetes in their patients and the International Diabetes Federation (IDF) estimated in 2017 that there were 451 million diabetics worldwide, representing as much as 8.8% of the population.
Zinc is a micronutrient commonly found in the human body and essential for its proper functioning. As a cofactor, it is part of more than 300 enzymes involved in, among other things, the processes of cell division and differentiation and regulation of gene expression. Zinc is involved in the metabolic transformation of proteins, fats and carbohydrates. It also exhibits antioxidant properties through its protective effect on the thiol groups that build amino acids and by stimulating the expression of glutathione and metallothioneins, i.e. molecules with antioxidant properties. It is also responsible for taste and smell, alcohol metabolism and the body’s immune defenses.
What is important for understanding the causes for the development of diabetes, zinc ions are found most abundantly in the beta cells of the pancreatic islands, where they play indispensable roles ranging from the proper synthesis of insulin, its storage in a stable form, to the proper secretion of this hormone. A screening study of people with type II diabetes showed proportionally reduced levels of this element in the blood in the context of this disease progression and glycemic status (Bandeira et al. 2017). Recent studies involving zinc point to its hypoglycemic and lipid profile-regulating effects, which could serve as a potential future tool for lowering blood glucose levels in diabetics as well as reducing oxidative stress and regulating metabolism (Jayawardena et al. 2012; Capdor et al. 2013). Also, the described micronutrient is credited with alleviating the resulting kidney damage, the development of cataracts and neuropathies or cardiovascular disease and also helps restore balance to the digestive system. (Donath & Shoelson 2011; Barman & Srinivasan 2019; Liu et al. 2014; Ranasinghe et al. 2015).
In conclusion, adequate zinc supplementation can facilitate diabetes management and thus reduce the risk of complications. The primary, non-pharmacological treatment of type II diabetes is lifestyle changes based on weight reduction, increased physical activity and a balanced diet. Foods rich in zinc include rye bread, cheese, meat, groats or eggs. Due to low bioavailability of this micronutrient from plant products relative to animal products, those following a vegan or vegetarian diet should consider additional supplementation with well-absorbable forms of mineral salts such as zinc bisglycinate (amino acid chelate), zinc gluconate or zinc lactate.
