• Commercial weight management organization;
  • effectiveness;
  • obesity

What is already known on this subject

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    There is growing evidence of the effectiveness of commercial weight management programmes in the community. A recent randomized controlled trial has shown commercial providers to be more effective than NHS providers for weight management solutions in primary care. Some commercial weight management providers have established national slimming on referral schemes for weight management, which result on average in weight losses of 4–5% over a 12-week referral period. A recent randomized controlled trial of a similar scheme over 12 months yielded similar weight loses. Another RCT comparing commercial providers over 6 months showed average weight losses of ∼6.6% across providers.

What this study adds

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    The present study shows that when local primary care practitioners target resources to where they, as health professionals, felt they would have the most beneficial effect in their local communities, greater weight losses can be achieved.
  • • 
    Different NHS Trusts extended 12-week referrals by an additional 12 weeks in a total of 4754 patients.
  • • 
    Mean weight losses of 8.6% were achieved suggesting that local targeting of primary care resources can maximize returns for NHS investments in commissioning the services of commercial weight management organizations.


This project audited attendance and weight loss in a primary care/commercial weight management partnership scheme in patients who participated over 6 months. 4754 adult patients (575 men, 4179 women) were referred to Slimming World for 24 weekly sessions. Data were analysed using individual weekly weight records. Mean (standard deviation, SD) body mass index (BMI) change was −3.3 kg m−2 (2.2), weight change −8.9 kg (6.0), percent weight change −8.6% (5.3) and number of sessions attended 21.3 (3.2) of 24. For patients attending at least 20 of 24 sessions (n = 3626 or 76.3%), mean (SD) BMI change was −3.6 kg m−2 (2.2), weight change −9.6 kg (6.1), percent weight change −9.3% (5.3). Weight loss was greater in men than women (P < 0.001). 74.5% of all patients enrolled, and 79.3% of patients attending 20 or more sessions achieved at least 5% weight loss. 37.3% of the whole population lost ≥10% of their weight. Weight gain was prevented in 96.3% of all patients referred. Referral to a commercial organization for community-based lifestyle intervention is a practical option for longer-term National Health Service weight management strategies.