[Obesity and diabetes mellitus]

New literature data and the results of own researches concerning the role of excessive body weight and the development of type 2 diabetes mellitus in humans are presented in the analytical review. Inaccordance with current insights, obesity and type 2 diabetes are considered diseases of inflammatory nature, characterized by systemic chronic low-grade inflammation, where different kinds of cytokines are cardinally involved. Unfavourable life style, i.e. excessive, high-energy, and irrational nutrition--an excessive consumption of animal fats and foods containing the high amount of glucose and starch with an insufficient use of high fiber vegetables, fish and vitamin D, and also sedentary, inactive life style leads to adipocyte hypertrophy and migration of M1 macrophages into the adipose tissue (AT). As a result, there is a low-grade inflammation accompanied by an increased production of proinflammatory cytokines (IL-1, IL-6, TNF-α, etc.), adipokines (leptin, resistin, visfatin etc.) and chemokines (CCL2, CCL5, CCL26 and CX3C). Under the influence of these cytokines, on the one hand, IR "is emerged", and on the other--there is apoptosis of the β-cells, that should be followed by the occurrence of clinically diagnosed type 2 diabetes. However, there is also the opposite system in humans, protecting the organism from the development of type 2 diabetes, and including an increase in the formation of M2 macrophages and the increased formation of secretion of antidiabetic cytokines (IL-4, IL-10, IL-13, etc.) and adiponectin.