Evaluating differences in the clinical impact of a free online weight loss programme, a resource-intensive commercial weight loss programme and an active control condition: a parallel randomised controlled trial

Background Finding effective intervention strategies to combat rising obesity levels could significantly reduce the burden that obesity and associated non-communicable diseases places on both individuals and the National Health Service. Methods In this parallel randomised-controlled trial, 76 participants who are overweight or obese (50 female) were given free access to a fitness centre for the duration of the 12-week intervention and randomised to one of three interventions. The commercial intervention, the Healthy Weight Programme, (HWP, n=25, 10/15 men/women) consisted of twelve 1-hour nutrition coaching sessions with a nutritionist delivered as a mixture of group and 1 to 1 sessions. In addition, twice-weekly exercise sessions (24 in total) were delivered by personal trainers for 12 weeks. The NHS intervention (n=25, 8/17 men/women) consisted of following an entirely self-managed 12-week online NHS resource. The GYM intervention (n=26, 8/18 men/women) received no guidance or formal intervention. All participants were provided with a gym induction for safety and both the NHS and GYM participants were familiarised with ACSM physical activity guidelines by way of a hand-out. Results The overall follow-up rate was 83%. Body mass was significantly reduced at post-intervention in all groups (HWP: N=18, -5.17±4.22 kg, NHS: N=21 -4.19±5.49 kg; GYM: N=24 - 1.17±3.00 kg; p < 0.001) with greater reductions observed in HWP and NHS groups compared to GYM (p<0.05). Out with body mass and BMI, there were no additional statistically significant time x intervention interaction effects Conclusions This is the first study to evaluate the efficacy of both a free online NHS self-help weight-loss tool and a commercial weight loss programme that provides face-to-face nutritional support and supervised exercise. The findings suggest that both interventions are superior to an active control condition with regard to eliciting short-term weight-loss.