Several expert panels have recommended the use of a body mass index (BMI = weight/height²) to assess obesity. Excessive risks of chronic diseases and mortality are clear when BMI exceeds 30 kg/m². Probably more important in assessing the health risks of excessive fat stores is the distribution of fat over the body. Accumulation of fat in the abdominal cavity (mesenteric and omental fat) predisposes to important metabolic aberrations and leads to an increased incidence of diabetes mellitus, cardiovascular disease, and stroke. Importantly, the increased risks associated with abdominal obesity are seen in obese as well as in non-obese individuals.