Jolly et al. BMC Public Health 2010, 10:439 http://www.biomedcentral.com/1471-2458/10/439 S T U D Y P R O T O C O L Open Access A randomised controlled trial to compare a range of commercial or primary care led weight reduction programmes with a minimal intervention control for weight loss in obesity: the Lighten Up trial Kate Jolly1*, Amanda Daley1, Peymane Adab1, Amanda Lewis2, John Denley3, Jane Beach3, Paul Aveyard1 Abstract Background: Developed countries are facing a huge rise in the prevalence of obesity and its associated chronic medical problems. In the UK Primary Care Trusts are charged with addressing this in the populations they serve, but evidence about the most effective ways of delivering services is not available. The aim of this study is to determine the effectiveness of a range of weight loss programmes for obese patients in primary care and to determine the characteristics of patients who respond to an invitation to a free weight management programme. Methods/Design: Lighten Up is a randomised controlled trial comparing a range of 12-week commercial and NHS weight reduction programmes with a comparator group who are provided with 12 vouchers enabling free entrance to a local leisure centre. The weight reduction programmes are: (i) Weight Watchers, (ii) Slimming World, (iii) Rosemary Conley, (iv) a group-based dietetics-led programme (Size Down), (v) general practice one-to-one counselling, (vi) pharmacy-led one-to-one counselling, (vii) choice of any of the 6 programmes. People with obesity or overweight with a co-morbid disorder are invited to take part by a letter from their general practitioner. The sample size is 740 participants. The primary outcome is weight loss at programme-end (3 months). Secondary outcomes are weight-loss at one year, self-reported physical activity at 3 and 12 months follow-up and percentage weight-loss at 3 months and one year. Discussion: This trial will provide evidence about the effectiveness of a range of different weight management programmes in a primary care population. Trial registration: Current Controlled Trials ISRCTN25072883 Background In the UK the rates of obesity have more than doubled in the last 25 years, and being overweight has become the norm for adults [1]. In 2003/2004, the mean body mass index (BMI) of men and women in the UK general population was 27 kg/m2, outside the healthy range of 18.5-25 kg/m2 [2]. Health Survey for England 2008 data showed that nearly a quarter of men (24%) and women * Correspondence: c.b.jolly@bham.ac.uk 1School of Health & Population Sciences, University of Birmingham, Birmingham B15 2TT, UK (25%) were obese [3], as defined by the World Health Organisation (WHO) criteria of a BMI ≥ 30 [4]. In addi- tion, levels of physical activity were very low with only 6% of men and 4% of women meeting the government’s current recommendations for physical activity [3]. A number of chronic medical conditions are associated with overweight and obesity, including type 2 diabetes, hypertension, coronary heart disease and stroke, meta- bolic syndrome, osteoarthritis and various cancers [2]. Health benefits have been reported with modest weight loss of 5-10% from lifestyle interventions, with a © 2010 Jolly et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.