Plain English Summary
Background and study aims
Two-thirds of all men and women In the UK are overweight, with a quarter also qualified as obese. Diseases associated with obesity are straining healthcare resources and have created an urgent need to identify effective weight loss strategies. Unfortunately, research has shown that although achieving weight loss in the short term (about 8-12 weeks) is achievable for many people, maintaining weight loss is more difficult, with the majority of people regaining lost weight in the medium term (e.g. about a year). Several factors have been identified which are thought to contribute to weight regain after weight loss, including for example altered appetite, food cravings and activity habits. What is notable is that adaptations to weight loss may persist during weight maintenance, providing an ongoing and unrelenting drive for people to regain lost weight. However, it is unclear to what extent these processes are activated and sustained in response to different interventions that have been shown to be effective in the short term.
Commercial organisations have exploited the large marketplace of consumers who seek formal support with their weight loss, and programmes from the leading commercial weight loss service providers in the UK (e.g. Weight Watchers, Slimming World, Rosemary Connelly) are supported by scientific evidence demonstrating their short (8-12 weeks) and medium term (12 months) effectiveness. For example, in 2011 a large study compared weight outcomes from commercial and NHS-based weight loss programmes. It was shown that the commercial programmes induced about 4.5 kg weight loss at 12 weeks, the majority of which was maintained at 12 months. Notably, a clinically significant weight loss of >5% was seen in one-third to almost one-half of all cases in the commercial programmes at 12 weeks. These commercial programmes, however, are costly as they involve a substantial amount of contact time with health advisors. To date there are no studies comparing commercial weight loss studies with effective exercise interventions that can be done with a lower amount of supervision time.
The main aim of the present study is to compare the short and medium term effectiveness of 12-week interventions involving a commercial intervention, standard NHS care provision, or a control condition involving free gym membership only.
Who can participate?
People aged 18-50 who are obese (BMI between 30 kg/m2 and 40 kg/m2), physically inactive and have not engaged on a programme of dieting/weight loss within the last 6 months.
What does the study involve?
Participants are randomly allocated to one of three groups: Healthy Weight Programme (HWP), NHS programme (NHS) or a gym only programme (GYM).
Those allocated to the HWP group initially spend about 90 minutes in total with a nutritional therapist and a personal trainer. The nutritional therapist reviews their diet diary and provides guidance on healthy eating, portion control and cooking methods. The personal trainer advises on exercise suited to healthy weight management. Nutritional support is provided via one-to-one sessions with a nutritional therapist at the start and end of the intervention period and five bi-weekly group sessions in weeks 2, 4, 6, 8 and 10. These educational sessions cover information on controlling hunger and portion sizes, emotional eating, how sleep and stress affect weight, weight loss myths, menu planning and making healthy choices when travelling, and what to do after completing the 12-week programme. Furthermore, exercise guidance is provided by a qualified exercise professional, with group sessions provided at least once a week between weeks 2 and 10. These sessions include a taster class (‘getting started’), a circuits class, body weight training, kettlebells, core conditioning, and optional specialist classes (e.g. spinning, body pump, body combat, Pilates, yoga, body balance).
Those in the NHS group are provided with a 45-minute orientation of the 12-week online NHS programme and basic information on healthy living. For participants who do not have access to this resource online, the guide is printed in full.
The GYM group is asked to use the gym at will. Activities are recorded via online booking and entry scanning. Personnel are available to collect additional activity data where required. Participants are familiarised with the guidelines for weight loss which they will use as a guide.
What are the possible benefits and risks of participating?
Participants stand to learn about their state of current health and wellbeing and are provided with advice and guidance on healthy weight practices. Participants also have access to a Nuffield Health Wellbeing Centre. As is the case with all interventions there are risks in participating. We may identify results of clinical significance requiring further medical investigation. Although the risk is very small there is the risk that participants respond adversely to exercise which in the worst case scenario could result in death. A full screening process, physical monitoring and expert personnel will ensure that this remains a minimal risk.
Where is the study run from?
Central Glasgow Nuffield Health Wellbeing Centre (UK)
When is the study starting and how long is it expected to run for?
July 2016 to January 2017
Who is funding the study?
Nuffield Health Research Group (UK)
Who is the main contact?
Dr Ben Kelly
A comparison of short- and medium-term weight loss following a commercial intervention vs an online NHS intervention and free gym membership: a randomised controlled trial
Participants engaged in the commercial weight loss programme stand to demonstrate greater weight loss after 12 weeks in comparison to an NHS or gym only group.
University of Bath 'REACH' ethics committee, 22/07/2016, ref: EP 15/16 259/283
Single-centre interventional randomised controlled trial
Primary study design
Secondary study design
Randomised controlled trial
Patient information sheet
Not available in web format, please use contact details to request a participant information sheet
Participants are randomised into three groups.
Those randomised to the HWP group will initially spend approximately 90 minutes in total with a nutritional therapist and a personal trainer. The nutritional therapist will review their diet diary and provide guidance on healthy eating, portion control and cooking methods. The personal trainer will assess the baseline data and will advise on exercise suited to healthy weight management which will include a multi-modal approach. For the HWP Group, nutritional support will be provided via one-to-one sessions with a nutritional therapist at the start and end of the intervention period and five bi-weekly group sessions in weeks 2, 4, 6, 8 and 10. These educational sessions will cover information on controlling hunger and portion sizes, emotional eating, how sleep and stress affect weight, weight loss myths, menu planning and making healthy choices when travelling, and what to do after completing the 12-week programme. Furthermore, exercise guidance will be provided by a qualified exercise professional, with group sessions provided at least once a week between weeks 2 and 10. These sessions will include a taster class (‘getting started’), a circuits class, body weight training, kettlebells, core conditioning, and optional specialist classes (e.g. spinning, body pump, body combat, Pilates, yoga, body balance).
Those in the NHS group will be provided with a 45-minute orientation of the 12-week online NHS programme and basic information on healthy living. This will not be altered in any way for the trial. For individuals who do not have access to this resource online, the guide will be printed in full.
The GYM group will be asked to use the gym at will. Activities are recorded via online booking and entry scanning. Personnel are available to collect additional activity data where required. The participant will be familiarised with the ACSM guidelines for weight loss which they will use as a guide.
Primary outcome measure
Body mass measured via Seca clinical grade weighing scale at the following timepoints: week -2 (pre screening), week 0 (baseline data collection), week 12 (post-intervention data collection), month 6 (6 months post-intervention), month 12 (12 months post-intervention)
Measured at week -2 (pre screening), week 0 (baseline data collection), week 12 (post-intervention data collection) only.
Secondary outcome measures
1. Blood glucose
These analytes will measured from whole blood sample and will be processed within a Nuffield Health Clinical Pathology Laboratory. Time points for whole blood analysis will be: week 0 (baseline data collection), week 12 (post-intervention data collection)
Overall trial start date
Overall trial end date
Reason abandoned (if study stopped)
Participant inclusion criteria
1. Apparently healthy males and females
2. Aged 18-50 years
3. BMI>30 kg·m-2
Target number of participants
Total final enrolment
Participant exclusion criteria
1. Having been on a diet during the past 6 months
2. Classification as highly physically active on the International Physical Activity Questionnaire (IPAQ)
3. Uncontrolled blood pressure >140/90 mm Hg
4. Total blood cholesterol >6.21 mM
5. Fasted blood glucose >6.1 mM
Recruitment start date
Recruitment end date
Countries of recruitment
Trial participating centre
Nuffield Health Research Group - Glasgow Central Team
Nuffield Health 141 Finnieston Street
University of Bath (UK)
Claverton Down Road
Nuffield Health Research Group (UK)
Funding Body Type
Funding Body Subtype
Results and Publications
Publication and dissemination plan
It is expected that this trial will lead to two separate publications. Paper 1 will detail results from the acute 12 week lifestyle intervention and will discuss the variation in results between experimental groups. Paper 2 will focus on weight maintenance specifically detailing changes in the primary outcome measure 12 months post-intervention.
IPD sharing statement:
The data sharing plans for the current study are unknown and will be made available at a later date.
Intention to publish date
Participant level data
To be made available at a later date
Basic results (scientific)
2019 results in ncbi.nlm.nih.gov/pubmed/31870345 (added 31/12/2019)