Obesity is a complex chronic disease that has become a major public health problem in many countries throughout the world because of its high prevalence, causal relationship with many serious medical illnesses, adverse effects on quality-of-life, and marked economic consequences related to increased health care costs and decreased productivity. Although obesity is defined as an excess amount of body fat, the threshold value that defines what amount of body fat is “unhealthy” is not clear and the ability to reliably measure body fat mass requires specialized equipment that is not readily available in most clinical settings.