Overweight and obesity are one of the most serious civilization threats of the 21st century. Despite the ever expanding knowledge involving the consequences associated with excessive body mass and high expenditure on the promotion of healthy lifestyles, statistics are reporting unfavorable results. The issue of obesity affects not only a highly developed countries but also developing ones. This is most likely due to an easy access and low prices of processed, high‑calorie food products. The immediate cause of obesity is the disturbance of the energy balance through supplying energy to the body in a quantity exceeding its demand. However, there are many factors predisposing to this disease and affecting its course. Obesity also poses a risk factor for many systemic diseases, from a widely described hypertension, diabetes and cancer. Excessive weight is observed in people of all races regardless of their age, both in women and men. This presents a serious health issue, doctors of all specialties should pay their attention to. The aim of this work is to present, based on the latest literature, issues related to epidemiology, causes and complications of obesity as well as diagnostic and therapeutic methods. Basic knowledge involving this extremely important problem will allow physicians of all specialties to holistically look at the health of their patients.

Key words: overweight, obesity.