Background: Obesity is a threaten to health due to its association with cardiovascular risk factors. Aim: To assess the change in metabolic risk factors after weight reduction in obese patients. Patients and methods: A retrospective analysis of 277 obese patients (198 female) aged 39.5±12 years old, that completed a six month treatment period, consisting in a calori restricted diet (800-1200 Kcal/day), physical activity, education and group psychological counseling. At the beginning and at the end of the program, weight, waist circumference, resting energy expenditure (REE), serum lipid profile, plasma glucose and plasma insulin levels were measured. Results: During the treatment period, body mass index decreased from 38±7 to 33.2±6.4 kg/m2 with a weight loss of 11.7 kg, waist circumference decreased from 106.6±14.6 to 93.9±13.5 cm, REE decreased from 1774±383 to 1585±267 Kcal/day, blood glucose fell by 5.8%, plasma insulin fell by 40.4%, total cholesterol fell by 7.5%, LDL cholesterol fell by 8.7%, triglycerides fell by 26.6%, and total cholesterol/HDL ratio fell by 12.2%. Conclusions: Weight loss was associated with improvement in metabolic cardiovascular risk factors in obese patients