Piloting a Generative Artificial Intelligence Chatbot in a Mobile Weight Loss Program

The goal of this study is to learn if integrating a chatbot into an existing 12-week smartphone-delivered behavioral weight loss program is feasible and effective for weight loss among young adults. Researchers will compare a standard behavioral weight loss program for young adults that delivers 1-2 brief messages per day (AGILE) to the same program with a chatbot that offers additional behavior change support integrated into the app (AGILE + Chatbot) to determine if the program with the chatbot is feasible, acceptable to participants, and improves program engagement and weight change compared to AGILE alone.

At baseline, 20 young adults, ages 18-39, with overweight or obesity, will be randomized to either the AGILE or AGILE + Chatbot group. Participants in both groups will receive a 12-week mobile behavioral weight loss intervention (AGILE) delivered via the study smartphone application. The weight loss intervention includes weekly evidence-based lessons; personalized goals; self-monitoring of diet, activity, and weight; weekly tailored feedback on progress; and brief, tailored messages 1-2 times per day displayed in the study smartphone app. Participants in the AGILE group will receive no additional program features. Participants in the AGILE + Chatbot group will have a version of the smartphone app with an integrated chatbot. The chatbot will be available for brief conversations 1-2 times per day. Assessments will occur at baseline and 12 weeks.

Inclusion Criteria: * body mass index (BMI) of 25-45 kg/m\^2 * English-speaking and writing * own an iPhone with a data plan * willing to be randomized to either treatment group Exclusion Criteria: * Type 1 diabetes or currently receiving medical treatment for Type 2 diabetes * Other health problems which may influence the ability to walk for physical activity or be associated with unintentional weight change, including tuberculosis, currently receiving cancer treatment, or history of a heart attack or stroke * Report a heart condition, chest pain during periods of activity or rest, or loss of consciousness on the Physical Activity Readiness Questionnaire (PAR-Q; items 1-4), or report any other reason not able to walk for physical activity * Lost 10 or more pounds (and kept it off) in the last 6 months * Currently taking weight loss medications * History of weight loss surgery or planning weight loss surgery in the next 4 months * Report a past diagnosis of, or receiving treatment for, a DSM-5-TR (Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, Text Revision) eating disorder (anorexia nervosa or bulimia nervosa) * Currently pregnant or planning to become pregnant within the next 4 months * Health or psychological diagnoses that preclude participation in a prescribed dietary and exercise program, including history of or diagnosis of schizophrenia or bipolar disorder, hospitalization for a psychiatric diagnosis in the past year, current diagnosis of alcohol or substance abuse * Another member of the household is a participant or staff member on this trial * Currently participating in a weight loss, nutrition, or physical activity study or program or other study that would interfere with this study * Not willing to wear a Fitbit every day * Have participated in another study conducted by the UNC Weight Research Program within the past 12 months