Obesity traditionally has been defined as a weight at least 20% above the weight corresponding to the lowest death rate for individuals of a specific height, gender, and age (ideal weight).. Excessive body weight has been shown to predispose to various diseases, particularly cardiovascular diseases, diabetes mellitus type 2, sleep disturbances (sleep apnea) and osteoarthritis. Obesity is one of the major risk factors for developing a heart attack, as well as hypertension and stroke.