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Meta-Analysis
. 2014 Oct;114(10):1557-68.
doi: 10.1016/j.jand.2014.07.005.

Diet or exercise interventions vs combined behavioral weight management programs: a systematic review and meta-analysis of direct comparisons

David J Johns, Jamie Hartmann-Boyce, Susan A Jebb, Paul Aveyard; Behavioural Weight Management Review Group
Meta-Analysis

Diet or exercise interventions vs combined behavioral weight management programs: a systematic review and meta-analysis of direct comparisons

David J Johns et al. J Acad Nutr Diet. 2014 Oct.

Abstract

Weight loss can reduce the health risks associated with being overweight or obese. However, the most effective method of weight loss remains unclear. Some programs emphasize physical activity, others diet, but existing evidence is mixed as to whether these are more effective individually or in combination. We aimed to examine the clinical effectiveness of combined behavioral weight management programs (BWMPs) targeting weight loss in comparison to single component programs, using within study comparisons. We included randomized controlled trials of combined BWMPs compared with diet-only or physical activity-only programs with at least 12 months of follow-up, conducted in overweight and obese adults (body mass index ≥25). Systematic searches of nine databases were run and two reviewers extracted data independently. Random effects meta-analyses were conducted for mean difference in weight change at 3 to 6 months and 12 to 18 months using a baseline observation carried forward approach for combined BWMPs vs diet-only BWMPs and combined BWMPs vs physical activity-only BWMPs. In total, eight studies were included, representing 1,022 participants, the majority of whom were women. Six studies met the inclusion criteria for combined BWMP vs diet-only. Pooled results showed no significant difference in weight loss from baseline or at 3 to 6 months between the BWMPs and diet-only arms (-0.62 kg; 95% CI -1.67 to 0.44). However, at 12 months, a significantly greater weight-loss was detected in the combined BWMPs (-1.72 kg; 95% CI -2.80 to -0.64). Five studies met the inclusion criteria for combined BWMP vs physical activity-only. Pooled results showed significantly greater weight loss in the combined BWMPs at 3 to 6 months (-5.33 kg; 95% CI -7.61 to -3.04) and 12 to 18 months (-6.29 kg; 95% CI -7.33 to -5.25). Weight loss is similar in the short-term for diet-only and combined BWMPs but in the longer-term weight loss is increased when diet and physical activity are combined. Programs based on physical activity alone are less effective than combined BWMPs in both the short and long term.

Keywords: Behavioral programme; Diet; Exercise; Obesity; Weight loss.

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Figures

Figure 3
Figure 3
PRISMA flow diagram of review process. aRCT=randomized controlled trial.
Figure 4
Figure 4
Mean difference in weight loss between behavioral weight management programs involving both diet and physical activity and programs involving diet only at 3 to 6 months. SD=standard deviation. IV=inverse variance. VLED=very-low-energy diet.
Figure 5
Figure 5
Mean difference in weight loss between behavioral weight management programs involving both diet and physical activity and programs involving diet only at 12 months. SD=standard deviation. IV=inverse variance. VLED=very-low-energy diet.
Figure 6
Figure 6
Mean difference in weight loss between behavioral weight management programs involving both diet and physical activity and programs involving physical activity only at 3 to 6 months. SD=standard deviation. IV=inverse variance.
Figure 7
Figure 7
Mean difference in weight loss between behavioral weight management programs involving both diet and physical activity and programs involving physical activity only at 12 to 18 months. SD=standard deviation. IV=inverse variance.
See this image and copyright information in PMC

References

    1. Finucane M.M., Stevens G.A., Cowan M.J. National, regional, and global trends in body-mass index since 1980: Systematic analysis of health examination surveys and epidemiological studies with 960 country-years and 9·1 million participants. Lancet. 2011;377(9765):557–567. - PMC - PubMed
    1. Kelly T., Yang W., Chen C.S., Reynolds K., He J. Global burden of obesity in 2005 and projections to 2030. Int J Obes. 2008;32(9):1431–1437. - PubMed
    1. World Health Organisation . World Health Organization; Geneva, Switzerland: 2009. Global Health Risks: Mortality and Burden of Disease Attributable to Selected Major Risks.
    1. World Cancer Research Fund . World Cancer Research Fund/American Institute for Cancer Research; Washington, DC: 2007. Food, Nutrition, Physical Activity, and the Prevention of Cancer: A Global Perspective.
    1. Whitlock G., Lewington S., Sherliker P. Body-mass index and cause-specific mortality in 900 000 adults: Collaborative analyses of 57 prospective studies. Lancet. 2009;373(9669):1083–1096. - PMC - PubMed