A qualitative investigation of individuals' experiences and expectations before and after completing a trial of commercial weight loss programmes

J Hum Nutr Diet. 2008 Feb;21(1):72-80. doi: 10.1111/j.1365-277X.2007.00837.x.


Objectives: To investigate the previous dieting experiences and expectations of individuals enrolled in a randomized trial of four commercial weight loss programmes and post-intervention to compare experiences across the diet groups.

Aim: The purpose of this study was to enhance the understanding of why subjects volunteered to take part in a weight loss trial and also to ascertain their views on each of the diets tested.

Methods: Focus groups containing both men and women were undertaken at baseline prior to randomization, and diet specific focus groups were held post-intervention. All group discussions were recorded and transcribed verbatim and analysed for emerging themes using the long-table approach.

Results: The main intrinsic motivators to enroling in the study were a current lack of self-esteem and confidence. The opportunity to take part in an academic study was also a motivator. Motivation and increasing efficacy were cited commonly among those who had successfully lost (or at least not gained) weight. The 'pros' identified for each of the commercial diets tested in the trial were in line with each of the diet's promotional materials; the 'cons' varied between groups.

Conclusion: In this study, reducing health risks was not the main motivator for people deciding to lose weight. Increasing intrinsic sense of worth gained by losing weight and continued motivation appear to be related to success. The differing experiences of people undertaking each of the four diets suggest that matching diet regimen to individual is important.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Cohort Studies
  • Diet, Reducing / psychology
  • Female
  • Focus Groups
  • Health Status
  • Humans
  • Male
  • Motivation*
  • Obesity / diet therapy*
  • Obesity / psychology*
  • Self Concept*
  • Self Efficacy
  • Treatment Outcome
  • Weight Loss*