What factors influence weight loss in participants of commercial weight loss programmes? Implications for health policy

Finding effective referral policies for weight management services would have important public health implications.Here we compare percentage weight change by referral methods, BMI categories and participants who have had attended weight loss programmes multiple times.A prospective cohort study of 15,621 participants referred to 12-week behavioural weight loss programmes funded by the public health service in Birmingham, UK.Comparisons were made between GP versus self-referrals, BMI ≥40kg/m2-<40kg/m2 and multiple referrals compared to only one referral. Linear mixed modelling was used to assess percentage weight change after adjusting for covariates.Participant's mean age was 48.5 years, 78.7% were of white ethnicity, 90.3% female and mean baseline BMI was 36.3kg/m2. There were no significant differences in percentage weight loss, between participants that self-referred and those that were referred by their general practitioner (GP) and no significant differences between baseline BMI categories. Referral to a weight loss programme more than once was associated with less weight loss at subsequent attendances (0.92%, 95% CI 0.70-1.14, p<0.001).Allowing self-referral to a weight loss programme widens access without compromising amount of weight lost. These programmes are beneficial for all categories of obesity, including those with a BMI ≥40kg/m2. Attending weight management programmes more than once results in less weight loss and that swapping to a different program may be advisable