Too committed to quit it! Can making a commitment help you achieve your diet and weight loss goals?

The Bottom Line

  • Globally, almost two billion adults are either classified as overweight or living with obesity, making them at greater risk for death and chronic disease development.  
  • Lifestyle changes around diet and exercise can be effective for weight loss, but people don’t seem to stick with strategies that assist them in these areas. 
  • Written soft commitment devices—such as behavioural contracts—used alongside other lifestyle change supports—such as weight loss programs—may help improve weight loss and dietary outcomes in adults who are overweight or living with obesity.
  • Consult your health care provider about the possibility of adding a soft commitment device to your weight loss plan. 

“Commitment is the foundation of great accomplishments.”

                                                                           —Dr. Heidi Reeder, Author and Professor

Be it losing weight, exercising more, or making better dietary choices; at one time or another, we’ve all had a health goal we’ve wanted achieve. However, those of us who’ve tried turning these hopes into a reality know that the road to success can be riddled with potholes and speed bumps.

Take, for example, the goal of weight loss. For the almost two billion people globally who are considered to be either overweight or living with obesity (1), whether or not they're able to attain this goal can have positive or negative implications on their risk of death and developing other chronic conditions. Nevertheless, just knowing that there are benefits to losing excess weight and consequences to keeping it on isn’t always enough to get the job done (1;6).

Have you, a friend, or a family member ever set a weight loss goal—perhaps as a New Year’s resolution or upon the recommendation of your health care provider? Take a second to reflect on this experience. Were you or they able to achieve it? If so, kudos! If not, ask yourself why?

The answer to the last question may be complex and individual to you or your loved one. Still, many of us find it hard to achieve weight loss goals because we must often make fundamental changes to the way we live—specifically around how we eat and our exercise behaviours (2;7:8). A particular area of struggle, which can contribute to lack of success, seems to be insufficient adherence to strategies that target these lifestyle changes (2;9). So, the question then becomes, is there a technique that we can use to help us stick to strategies that drive lifestyle change? A recent systematic review looking at commitment making aimed to find out (2).

What the research tells us

The review specifically investigated commitment making through the use of ‘soft commitment devices’ in adults who were overweight or living with obesity. These devices are essentially strategies—such as written pledges, behavioural contracts, or verbal agreements—that help you commit to attaining a chosen outcome or carrying out a desired behaviour, but without receiving incentives or rewards to do so. Within the review, written soft commitment devices—generally behavioural contracts—were combined with other lifestyle change supports such as educational weight loss programs.

Ultimately, it was found that soft commitment devices may hold potential benefits for weight loss and diet changes, but not exercise. Increases in weight loss were seen both in the short-term (up to six months) and long-term (up to 12 months). In the short-term, those who used a soft commitment device lost an average of 1.52 kg more than those who received no treatment or information only. In the long-term, an average 1.7 kg more weight was lost. Short-term improvements to diet in the form of reducing calorie intake, increasing consumption from more healthy food groups, and reducing consumption from unhealthy food groups were also seen. What’s more, some evidence supports including a public component to this strategy, such as having a peer or health care provider witness the commitment being made. Ultimately, if your focus in on weight loss and improving your diet, commitment making through soft commitment devices may be helpful for you.

Although the benefits highlighted by this review are encouraging, it should be noted that many of the results were based on a small number of studies. This means more high-quality research is needed to confirm these findings and gain a better understanding of the most effective characteristics of soft commitment devices (2).

Looking to add an extra layer of accountability as you move through your weight loss journey? Speak with your health care provider about the benefits of commitment making and the best way to incorporate this technique into your weight loss plan.

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Author Details


  1. World Health Organization. Obesity and overweight. [Internet] 2020. [cited August 2020]. Available from 
  2. Coupe N, Peters S, Rhodes S, et al. The effect of commitment-making on weight loss and behaviour change in adults with obesity/overweight; A systematic review. BMC Public Health. 19(1):816. doi: 10.1186/s12889-019-7185-3. 
  3. Poobalan AS, Aucott LS, Smith WCS, et al. Longterm weight loss effects on all cause mortality in overweight/obese populations. Obes Rev. 2007; 8(6):503-513. doi: 10.1111/j.1467-789X.2007.00393.x.
  4. Wing RR, Lang W, Wadden TA, et al. Benefits of modest weight loss in improving cardiovascular risk factors in overweight and obese individuals with type 2 diabetes. Diabetes Care. 2011; 34(7):1481-1486. doi: 10.2337/dc10-2415.
  5. Ratner R, Goldberg R, Haffner S, et al. Impact of intensive lifestyle and metformin therapy on cardiovascular disease risk factors in the diabetes prevention program. Diabetes Care. 2005; 28(4):888-894. doi: 10.2337/diacare.28.4.888. 
  6. World Cancer Research Fund International. Body fatness and weight gain and the risk of cancer. [Internet] 2018. [cited August 2020]. Available from 
  7. Franz MJ, VanWormer JJ, Crain AL, et al. Weight-loss outcomes: A systematic review and meta-analysis of weight-loss clinical trials with a minimum 1-year follow-up. J Am Diet Assoc. 2007; 107(10):1755-1767. doi: 10.1016/j.jada.2007.07.017.
  8. Swift DL, Johannsen NM, Lavie CJ, et al. The role of exercise and physical activity in weight loss and maintenance. Prog Cardiovasc Dis. 2014; 56(4):441447. doi: 10.1016/j.pcad.2013.09.012. Epub 2013 Oct 11.
  9. Heymsfield SB, Harp JB, Reitman ML, et al. Why do obese patients not lose more weight when treated with low-calorie diets? A mechanistic perspective. Am J Clin Nutr. 2007; 85(2):346-354. doi: 10.1093/ajcn/85.2.346.

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