Obesity is a chronic disease that is caused by many different factors and is the cause of numerous complications. Obesity poses a serious health risk and is defined as an excessive amount of fat accumulation in a person's organism - with a Body Mass Index (BMI) over 30 kg/m² as defined by the World Health Organization.
Obesity is a known risk factor for chronic diseases including heart disease, diabetes, high blood pressure, sudden stroke, and some types of cancer.
Research suggests that obesity has a multiple factor origin. Some of these factors include genetic, environmental, and psychological, which cause an abnormal or excessive fat accumulation in the body - an overgrowth of fat tissue.