Purpose The purpose of the study was to examine the long-term effect of a Group Lifestyle Balance (GLB) program on weight, impaired fasting glucose, hypertension, and hyperlipidemia in an urban, medically underserved community. Methods This study was a single-arm prospective intervention study that was designed to test the effectiveness of a community-based GLB intervention. In sum, 638 residents from 11 targeted neighborhoods were screened for body mass index ≥ 25 kg/m² and metabolic syndrome. Eligible individuals took part in a 12-week GLB intervention (n = 105) that addressed weight loss and physical activity. Subjects were followed for 24 months. Results The probability of being at risk for diabetes and cardiovascular disease was significantly reduced by 25.7% over the long-term follow-up. Of the participants who lost at least 5% of their body weight following the intervention, 52.6% maintained the 5% weight loss at their last follow-up time, weighing about 20 lb less than they did at baseline. Conclusion Risk reduction and weight loss maintenance are possible following a GLB intervention and have substantial potential for future public health impact.