Obesity is a major public health and socioeconomic burden. Outpatient obesity clinics are an essential resource for obese individuals to access lifestyle advice for weight loss management. The objective of the study was to determine the effectiveness of an outpatient obesity clinic in achieving weight loss outcomes based on dietary and exercise interventions. Data from 276 obese adults admitted to a multidisciplinary weight management clinic were retrospectively obtained. Changes in anthropometry, body composition and blood pressure from baseline to 12-months were statistically analysed. Treatment groups consisted of two dietary interventions (general dietary advice and very low calorie diet (VLCD)), in addition to an exercise intervention group. Linear mixed-effects models showed that general dietary advice for males produced statistically significant reductions in body weight, body mass index (BMI), waist and hip circumference, per cent fat mass and systolic blood pressure (p<0.01), however changes in males on VLCD did not reach significance. Females on both dietary interventions showed statistically significant reductions in body weight, BMI, waist and hip circumference, (p<0.01) and general dietary advice significantly reduced per cent fat mass (p<0.001). Females on VLCD produced statistically better reductions in body weight, BMI and systolic blood pressure than those on general dietary advice. No effect of exercise physiologist intervention was observed in this study. Results from this study indicate a positive effect of outpatient obesity clinics in facilitating clinically significant weight loss.