Currently submitted to: JMIR mHealth and uHealth
Date Submitted: Oct 16, 2025
Open Peer Review Period: Oct 28, 2025 - Dec 23, 2025
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Autonomous Digital Lifestyle Intervention for Obesity: A Comparative Study of Software-Generated vs. Provider-Delivered Body Composition Outcomes
ABSTRACT
Background:
Software-based interventions have emerged as effective tools for managing chronic diseases. Lifestyle intervention (LI) apps can promote weight loss, but many depend on human coaches or healthcare providers, thus introducing higher costs and variability in feedback. Most existing apps rely on calorie-counting approaches and lack structured, individualized guidance, leaving users to determine how to translate general recommendations into daily nutrition and exercise practices. Moreover, many do not provide rapid, adaptive feedback to adjust meal or activity plans in real time.
Objective:
To compare the RightBMI App, an autonomous, protein-focused digital lifestyle intervention, with provider-delivered lifestyle intervention (LI) for weight loss and body composition changes in bariatric surgery candidates.
Methods:
A prospective randomized trial (April 2024 - April 2025, Holyoke Medical Center) enrolled 160 patients (App: n=80; no-App: n=80). RightBMI provided personalized nutrition and exercise plans. Outcomes (% total body weight loss [%TBWL], % fat mass loss [%FML], % visceral fat loss [%VFL], % muscle mass loss [%MML]) were assessed over 24 weeks using Generalized Estimating Equations (GEE) with multiple imputation, adjusting for age, BMI, and sex (no-App as reference).
Results:
GEE models showed significant time effects for %TBWL (week 8: coefficient 2.91, p<0.001; week 24: 18.12, p<0.001) and %FML (week 8: 5.30, p<0.001; week 24: 33.65, p<0.001) in the no-App group. The App group had greater %TBWL at weeks 12 (2.64%, p<0.001) and 16 (2.47%, p=0.027), and %FML at weeks 12 (2.94%, p=0.028) and 16 (4.20%, p=0.003). At week 24, outcomes were comparable: App group (%TBWL: 20.01%, %FML: 36.81%, %VFL: 31.99%, %MML: -0.09%) vs. no-App (%TBWL: 19.97%, %FML: 35.74%, %VFL: 32.97%, %MML: 0.70%; all p>0.89). Both groups maintained stable %MML with %TBWL ~20% and %FML >32%. User satisfaction was high (8.76/10).
Conclusions:
The RightBMI App outperformed provider-led LI at mid-study, achieving comparable 24-week weight loss (~20%) and muscle preservation. With 90% bariatric surgery clearance (vs. 71.25% no-App) and low dropout (3.75% App, 1.25% no-App), RightBMI is a scalable, effective tool for obesity management.
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