Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) induce clinically meaningful weight loss, but their real-world impact is constrained by poor medication persistence, treatment-limiting gastrointestinal adverse effects, and rapid weight regain after cessation. These limitations may be structural rather than incidental: GLP-1 RAs powerfully address appetite biology but do not build the behavioral skills, environmental supports, and routines needed to sustain outcomes when biological pressures revert to baseline. This viewpoint argues that theory-based digital health companion programs are best understood as structural complements to glucagon-like peptide-1 (GLP-1) therapy rather than optional adjuncts, and it articulates a testable mechanistic hypothesis: a pharmacologically enabled "habit window." We map theoretical determinants from the social cognitive theory (SCT) and behavioral economics (BE) to classes of digital intervention across 3 problems (medication persistence, tolerability, and postcessation durability) and grade the supporting evidence as established, observational, or hypothesized. For each problem, we link candidate SCT- and BE-informed mechanisms (such as self-efficacy and enactive mastery, present bias, defaults, and loss aversion) to specific digital intervention classes and to the studies needed to test them. Because reduced appetitive drive may free cognitive resources and lower the need for food-related self-control, GLP-1 therapy may open a privileged window in which habit formation is easier. Supporting evidence is drawn from adjacent behavioral trials, combined pharmacological and lifestyle trials, and observational engagement data; the observational data are hypothesis generating and subject to selection effects. Digital behavioral infrastructure may help translate the biological effects of GLP-1 therapy into durable behavioral and environmental change, but the "habit window" remains a hypothesis requiring prospective and randomized testing. We outline a research agenda prioritizing randomized trials with postcessation follow-up and mechanistic mediation studies.
GLP-1 Therapies