About this Resource
When seeking weight loss, the common prescription is diet and exercise. However, it is often easier to limit energy intake rather than increase energy expenditure, suggesting that diet may be a more important factor than exercise for weight loss. This handout reviews the clinical trials which have explored whether diet or exercise is more important for achieving weight loss goals.
Grounded in the Research
“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.”
Excerpt from: Johns, D. J., Hartmann-Boyce, J., Jebb, S. A., Aveyard, P., & Behavioural Weight Management Review Group. (2014). Diet or exercise interventions vs combined behavioral weight management programs: a systematic review and meta-analysis of direct comparisons. Journal of the Academy of Nutrition and Dietetics, 114(10), 1557-1568.
References
[1] Miller, W. C., Koceja, D. M., & Hamilton, E. J. (1997). A meta-analysis of the past 25 years of weight loss research using diet, exercise or diet plus exercise intervention. International Journal of Obesity, 21(10), 941-947. https://doi.org/10.1038/sj.ijo.0800499
[2] Johns, D. J., Hartmann-Boyce, J., Jebb, S. A., Aveyard, P., & Behavioural Weight Management Review Group. (2014). Diet or exercise interventions vs combined behavioral weight management programs: a systematic review and meta-analysis of direct comparisons. Journal of the Academy of Nutrition and Dietetics, 114(10), 1557-1568. https://doi.org/10.1016/j.jand.2014.07.005
[3] Adegboye, A. R. A., & Linne, Y. M. (2013). Diet or exercise, or both, for weight reduction in women after childbirth. Cochrane Database of Systematic Reviews, (7). https://doi.org/10.1002/14651858.CD005627.pub3
[4] Thomas, D. M., Bouchard, C., Church, T., Slentz, C., Kraus, W. E., Redman, L. M., … & Heymsfield, S. B. (2012). Why do individuals not lose more weight from an exercise intervention at a defined dose? An energy balance analysis. Obesity Reviews, 13(10), 835-847. https://doi.org/10.1111/j.1467-789X.2012.01012.x
[5] Bellicha, A., van Baak, M. A., Battista, F., Beaulieu, K., Blundell, J. E., Busetto, L., … & Oppert, J. M. (2021). Effect of exercise training on weight loss, body composition changes, and weight maintenance in adults with overweight or obesity: An overview of 12 systematic reviews and 149 studies. Obesity Reviews, 22, e13256. https://doi.org/10.1111/obr.13256
[6] Weinheimer, E. M., Sands, L. P., & Campbell, W. W. (2010). A systematic review of the separate and combined effects of energy restriction and exercise on fat-free mass in middle-aged and older adults: implications for sarcopenic obesity. Nutrition Reviews, 68(7), 375-388. https://doi.org/10.1111/j.1753-4887.2010.00298.x