Introduction and objective:
Obesity and cancer are lifestyle diseases that are among the greatest challenges for medicine in the 21st century. Excess body weight, next to smoking and alcohol consumption, is one of the most important etiological factors predisposing to the development of oncological diseases. Currently, approximately one third of malignant tumours are located in the gastrointestinal tract. The aim of this study is to review the literature on obesity and its relationship with the process of carcinogenesis. Articles published between 2016–2024 were analyzed.

Abbreviated description of the state of knowledge:
The relationship between obesity and cancer is complex. In the pathophysiology of this phenomenon many co-occurring factors must be taken into account. Disturbances in the amount of hormones and growth factors, caused by excessive amounts of adipose tissue, come to the fore. Obesity, as a chronic inflammatory process, causes damage to the DNA structure in cells, which may initiate the mechanism of carcinogenesis. Excessive body weight is often accompanied by an incorrect lifestyle – poor diet and deficit of physical exercise. Moreover, obese patients usually suffer from cardiac diseases or type II diabetes, which contributes to a worse prognosis in oncological diseases.

Summary:
Taking into account the increasing incidence of digestive system cancers and their undeniable connection with obesity, it is necessary to introduce preventive actions, consisting primarily in increasing public awareness of this disease and the health consequences it carries. Nutritional education should be introduced and obese patients should be encouraged to change their lifestyle, because weight loss reduces the risk of developing many malignant tumours.