Body Mass Index, commonly abbreviated to BMI, is an easy way for doctors to assess how overweight or obese a patient is. BMI is calculated from your height and weight using a mathematical formula:
BMI = weight in kg / height in metres 2
BMI results are categorised as follows:
BMI is a good way of assessing body fat levels for the average person. One should bear in mind that it is just an average and does not take into account muscle mass. This means that the BMI for muscular people is an overestimate of their body fat. Conversely, for the elderly and other groups who have less muscle, the calculation may underestimate the true BMI.
Another way of assessing obesity is to measure your waist size. Coronary heart disease is known to be associated with a large waist size, which indicates an accumulation of fat in the central region of the body. Those at risk have a waist measurement in excess of 37" (94cm) for men and 32"(80 cm) for women. However, those at greatest risk have waist measurements in excess of 40" (102 cm) for men and 35" (88 cm) for women.