Obesity disproportionately impacts sexual minority women. Behavioral weight loss programs are the gold standard treatment for mild to moderate obesity. The investigators have developed an online behavioral weight loss program that is effective, low-cost, and highly scalable. However, existing research suggests that tailoring treatment to address 3 well-established weight loss barriers in sexual minority women will be critical for maximizing the relevance and efficacy of behavioral weight loss for this group. The goal of the first phase of this K23 is to develop 3 novel treatment components targeting sexual minority women's weight loss barriers (i.e., minority stress, low social support, and negative body image), to pilot the program in sexual minority women with overweight/obesity, and to conduct individual qualitative interviews to elicit feedback on the intervention's acceptability, cultural relevance, usability, and feasibility that will be used to refine the program. After a pre-piloting phase (consisting of initial content piloting, interviews, and intervention refinement; anticipated n=12), 8 participants will pilot the full 3-month weight loss program and will be randomized to pilot 0-3 novel tailored components (targeting minority stress, negative body image, and social support) over the 3-month period. Participants will complete quantitative and qualitative assessments of intervention acceptability and appropriateness post-treatment and the intervention will be refined.

Inclusion Criteria:

• Assigned female at birth and currently identify as female
• Self-identify a minority sexual orientation (e.g.,lesbian, bisexual)
• BMI>25kg/m2
• 18-70 years old
• Interested in losing weight
• Regular internet and e-mail access
• Fluent in English

Exclusion Criteria:

• Significant weight loss within past 6 months (>5%)
• Unable to participate in moderate physical activity
• Currently enrolled in a weight loss program
• Currently taking weight-loss medication
• Currently pregnant or trying to get pregnant
• Participated in a previous Phase of this study
• Reports a serious mental/physical health condition that would increase potential risks of treatment to the participant (e.g., active symptoms of psychosis, suicidality, mania, alcohol/substance use, or a medical condition that is serious, active, unstable, and degenerative (e.g., CHF)).

Participants who currently self-identify as female are being recruited.

Data will be shared as follows:

• Results will be submitted to ClinicalTrials.gov within appropriate timelines.
• Quantitative data will be published in peer-reviewed manuscripts that will be submitted to PubMed Central upon acceptance.
• Study results will be presented to the scientific community at national conferences relevant to obesity and sexual minority health.
• Aggregate quantitative data may be requested from other researchers 5 years after the completion of the primary endpoint by contacting Dr. Panza. If there are no restrictions imposed by institutional policies, local IRBs, or laws/regulations, the investigators will make de-identified data available to a requester within the context of a clear data-sharing agreement Qualitative data will not be shared other than de-identified qualitative data that is published as part of peer-reviewed manuscripts.

There is no masking during the pilot phase where the goal is to improve the program's acceptability.