Adjustment of Unrealistic Weight Loss Expectations on a Mobile CBT-Based Behavior-Change Program: Prospective One-Armed Study

Abstract

Background: Moderate weight loss of 5–10% is considered a realistically achievable weight loss goal and is associated with decreased risk of obesity-related health complications. However, individuals tend to expect that they will lose as much as 20–30% of their body weight when they start a behavioral weight loss program. Current research is limited on how these expectations change over time during weight loss and the consequences of adjusting one’s expectations in a more realistic direction, particularly on a CBT-based program. Method: Therefore, this prospective cohort study evaluated whether individuals adjusted their weight loss expectations over time during real-world use of a mobile CBT-based behavior-change program (Noom Weight) and how this adjustment related to weight loss outcomes, as well as how the amount of adjustment depended on program engagement. Participants had recently signed up for Noom Weight and reported their weight, expectations for weight loss, and psychological well-being at baseline and six months. Engagement was automatically recorded by the program. Results: We found that after using Noom Weight for six months, participants’ expectations became more realistic (i.e., significantly decreased) compared to baseline (−5.77, s.e. = 0.57, p < 0.001), and this downward adjustment was associated with greater weight loss (b = 1.80, 95% CI 1.21–2.38, p < 0.001). Higher program engagement, particularly reading articles focused on CBT-based principles, was associated with greater decreases in expectations over time (b = −0.007, t = −2.22, p = 0.03). Conclusions: The results suggest that CBT-based principles may aid in adjusting weight loss expectations to more realistic levels and that such adjustment is associated with positive weight outcomes. Future research should build on these results by evaluating adjustment in weight loss expectations over time, rather than solely expectations at baseline.