Objectives To assess the long-term effects on weight reduction and health of a group-based behavioral weight intervention over six months focusing eating for fulfillment as compared to a control regime with brief intervention.Method Overweight or obese adults (n = 176, 80% female, mean BMI 33.8 +/- 4.7 kg/m2, mean age 55.2 +/- 10.1 years) were randomized to a group treatment or control receiving a brief intervention. Ninety-three participants (53% of original sample) completed the 5-year follow-up. Anthropometrics, blood pressure and biochemical measurements, self-rated lifestyle habits, quality of life and medication were obtained at baseline, at the end of the 6-month intervention, and once a year for five years following randomization.Results A per-protocol analysis, performed due to a high drop-out rate, found that weight reduction was small and similar in the two groups after five years. Reduction of waist/hip ratio, total-cholesterol and triglycerides were somewhat larger in the control group than in the treatment group. No changes regarding blood pressure, quality of life or medication use between the treatment and control groups were found.Conclusions No effect on weight reduction of the group intervention was found as compared to brief intervention but both groups achieved small weight loss over time. Findings indicate that any intervention or merely regular follow-ups might be promotive for weight maintenance in middle age.