Obesity is a chronic disease that can lead to medical and psychological complications, including cardiovascular diseases, impaired glucose tolerance, chronic inflammations and visceral fatness. Obesity and sedentary lifestyle affect the morphology of osteochondral structures and the growth plate, leading to serious orthopaedic consequences. The stigma of obese children also increases the rates of anxiety disorders, depression and learning disabilities in the paediatric population. The COVID-19 pandemic has enforced the introduction of isolation rules, changing the living conditions of society. Working and studying remotely and keeping social contacts to a minimum resulted in a lower intensity of physical activity and altered eating habits, which significantly contributed to further weight gain in overweight and obese children. In the case of severe acute respiratory syndrome caused by coronavirus infection, organic changes associated with obesity may increase the risk of thromboembolism, reduce the glomerular filtration rate of the kidneys and increase the inflammatory response of the body, which may consequently lead to invasive mechanical ventilation. Previous studies on obesity in children have shown that a high inflammatory index increases the risk of long-term complications in severe acute respiratory syndrome coronavirus 2 infection and reduces the chances of a quick recovery. It is necessary to make the society aware of the extent of health complications of childhood obesity, introduce social education on the principles of nutrition, and facilitate access to holistic treatment for obesity. All tasks in the field of obesity prevention and treatment have been developed as part of the prevention programme.