Obesity is a disease of civilisation, with which an increasing number of the population is struggling - in Poland, it affects 19% of the population. The condition is chronic and is characterised by excessive accumulation of body fat (more than 15% of the body weight of an adult male and more than 25% of the body weight of an adult female). Obesity is not only caused by excessive eating (rich in sugars and fats), psychological factors (e.g. overeating stress), but also genetic predisposition (lack of genes that are responsible for normal metabolism).