Derive the body mass index (BMI) by nomogram or calculation (BMIweight in kg/height in m2). Overweight is defined as a BMI25 and obesity as a BMI30. Excess adipose tissue in the truncal region is an important cardiovascular disease risk factor, and it adversely affects blood pressure, cholesterol (total, HDL, and LDL), and triglyceride levels and glucose tolerance. Truncal obesity can be assessed and treatment can be monitored by estimating the weight/hip ratio (circumference of waist at umbilicus/circumference of hips at widest part; it is normally 1.0 in men and 0.85 in women) or by measuring girth horizontally at the level of the umbilicus (normally 94 cm in men and 80 cm in women). Truncal obesity syndrome is often accompanied by some or all of the following features: high plasma triglycerides, low HDL cholesterol, type 2 diabetes, hypertension, and an increased risk of CHD. A key mechanism is insulin resistance. Reducing overweight is often highly effective against all features of the syndrome.