health "condition". A person is considered "obese" when he or she weighs 20% or more than his or her ideal body weight. At that point, the person's weight poses a real health risk. Obesity becomes "morbid" when it significantly increased the risk of one or more obesity related health conditions or serious diseases. Morbid obesity - sometimes called "clinically severe obesity" - is defined as having a Body Mass Index (BMI) of 35 or higher.