The Effects of Water and Non-Nutritive Sweetened Beverages on Weight Loss During a 12-week Weight Loss Treatment Program

Publication Name: Obesity, 2014 June; 22(6): 1415–1421.

Author(s): Peters JC, Wyatt HR, Foster GD, Pan Z, Wojtanowski AC, Vander Veur SS, Herring SJ, Brill C, Hill JO | Publication Year: 2014


Objective: To compare the efficacy of non-nutritive sweetened beverages (NNS) or water for weight loss during a 12-week behavioral weight loss treatment program. Methods: An equivalence trial design with water or NNS beverages as the main factor in a prospective randomized trial among 303 men and women was employed. All participants participated in a behavioral weight loss treatment program. The results of the weight loss phase (12 weeks) of an ongoing trial (1 year) that is also evaluating the effects of these two treatments on weight loss maintenance were reported. Results: The two treatments were not equivalent with the NNS beverage treatment group losing significantly more weight compared to the water group (5.95 kg versus 4.09 kg; P < 0.0001) after 12 weeks. Participants in the NNS beverage group reported significantly greater reductions in subjective feelings of hunger than those in the water group during 12 weeks. Conclusion: These results show that water is not superior to NNS beverages for weight loss during a comprehensive behavioral weight loss program.


The results of this study suggest that water is not superior to non-nutritive sweetened (NNS) beverages for weight loss, in the context of a comprehensive behavioural weight loss plan. The purpose of this trial was to directly compare water, the “gold standard” beverage for supporting good health, with NNS beverages in the context of weight loss. This 1-year prospective, randomized trial included an equivalence design in which study groups received either water or NNS beverages. The trial includes a 12-week weight loss phase, followed by a 9 month weight maintenance phase. The results of the weight loss phase are presented in the current article. During the study, all 303 participants (279 completed the study) received a comprehensive, cognitive-behavioural weight loss intervention entitled, The Colorado Weigh, which included group meetings, instruction on behavioural weight loss strategies and weekly weigh-ins. Each participant was also given calorie targets, as well as weekly physical activity targets. Paired comparison between the two study groups indicated that the NNS group had lost significantly more weight than the Water group after 12 weeks (5.95 kg vs 4.09 kg (13.1 lbs vs. 9.0 lbs). In the NNS group 64.3% of participants lost > 5% of their of body weight, as compared to 43.0% of participants in the Water group. The authors concluded that their results suggest that NNS beverages can be part of an effective weight loss strategy, and that the consumption of such beverages will not undermine short-term weight loss efforts. A longer term follow-up of this randomized cohort is currently underway, and should provide insight into the utility of NNS beverages in weight loss maintenance.