Impact of obesity on total and cardiovascular mortality--fat or fiction?

Obesity is an excessive accumulation of fat that can impair health. Because the direct measurement of body fat is difficult to perform, a number of anthropometric measures have been employed as surrogates, of which BMI is the most commonly used. However, its usefulness has been questioned as a BMI in the overweight and mildly obese range is associated with improved survival and fewer cardiovascular events than a BMI in the normal range, a phenomenon known as the 'obesity paradox'. Waist circumference, waist-to-hip ratio, and waist-to-height ratio take into consideration body-fat distribution, especially abdominal obesity, and seem to predict cardiovascular risk better than does BMI.