More than 160 million American adults are overweight or obese. Existing weight loss interventions from self-help to gold standard behavioral treatments, while often effective, do not sufficiently maintain motivation to adhere to dietary goals in the face of powerful biological and environmental influences to consume highly palatable foods. Clarification and awareness of values, a staple of acceptance-based treatments drawn from Acceptance and Commitment Therapy, are thought to enhance autonomous motivation to engage in behaviors consistent with one's personal life values (e.g., health) in the presence of countervailing forces (e.g., hunger, deprivation). However, the independent efficacy of values clarification and awareness in facilitating weight control has never been tested. This pilot study seeks to investigate the feasibility and acceptability of a series of three weight loss workshops (based off the gold standard) infused with values clarification and awareness techniques to promote weight control. Participants will be asked to follow a reduced-calorie dietary prescription while holding their values in mind in moments of dietary decision-making over the course of one month. The primary aims of this study are to: 1) develop the series of values-infused workshops, using participant feedback to iterate and improve the treatment manual; and 2) evaluate treatment acceptability. Secondary aims are: 1) to evaluate whether clinically meaningful changes in measures of values clarification and values awareness occur; 2) to evaluate whether the intervention will lead participants to experience clinically meaningful changes in values-congruent weight control behaviors; 3) to evaluate whether the intervention will lead participants to experience clinically meaningful changes in weight; and 4) to evaluate theorized mechanisms of action in the intervention.

Inclusion Criteria:

• BMI of 25-55 kg/m2
• 18-70 years of age
• Have a desire to lose weight
• Own a smartphone
• Live in the Philadelphia area
• Provide informed consent

Exclusion Criteria:

• Any medical or psychiatric conditions (e.g., eating disorder, diabetes) that may pose a risk to the participant during the intervention, cause a change in weight or appetite, or interfere with ability to adhere to diet recommendations
• Recent change in medication dosage that could affect weight or appetite
• Current or planned pregnancy in the next month
• Planned move out of the Philadelphia area in the next month
• History of bariatric surgery
• Weight loss of ≥5% in the last six months
• Concurrent behavioral therapy targeting weight control