This study critically examined the relationships between weight loss and changes in serum lipid and blood pressure levels.Eighty morbidly obese women and men were treated with an intensive very-low-calorie diet (VLCD) and behavioral education program. Body weight and blood pressure were measured weekly. Serum lipids were measured biweekly.Patients lost an average of 35.3 kg in 25.6 weeks. These values decreased significantly: fasting serum cholesterol, 15.1%; low density lipoprotein cholesterol, 17.0%; triglycerides, 14.2%; systolic blood pressure, 8.7%; and diastolic blood pressure, 10.2%. Changes in serum lipids and blood pressure were significantly (p<0.001) correlated with baseline values and with changes in body mass index (BMI) after adjustment for baseline values. Patients maintained an average of 19.7 kg of their weight loss at the 2-year follow-up.Weight reduction through a multidisciplinary VLCD program significantly reduces risk factors for cardiovascular disease; for morbidly obese individuals, improvements in risk factors were significantly and linearly related to changes in the BMI.