Date of Completion


Embargo Period


Major Advisor

Amy A. Gorin, Ph.D.

Associate Advisor

Dean G. Cruess, Ph.D.

Associate Advisor

Linda S. Pescatello, Ph.D.

Field of Study



Doctor of Philosophy

Open Access

Campus Access


There is strong imperative to develop weight loss interventions that address the obesity epidemic. Social networks influence weight, and romantic partners are uniquely positioned to promote weight loss. Efforts to include partners in behavioral weight loss treatment have been disappointing, with little theoretical grounding on how best to foster support. Self-determination Theory (SDT) offers suggestions for how to effectively incorporate partners, positing that support for an individual’s autonomy is beneficial to fostering autonomous motivation and behavior change. Before developing SDT-informed interventions, an important goal for researchers is to learn from couples about what is helpful and harmful in the exchange of support for weight loss. The present studies sought to: 1) qualitatively evaluate the type of support exchanged between romantic partners in focus groups with couples; and 2) quantitatively elucidate characteristics and behaviors of partners that are perceived as supportive for weight loss. To address these aims, focus groups with romantic couples were conducted and six-month support outcomes of a randomized controlled intervention involving 132 spouses were evaluated. Results from the qualitative study indicated that main participants perceived their partners’ helpful behaviors as those that were collaborative, autonomy supportive, and empathic. Main participants perceived directive behaviors as unhelpful while partners perceived those actions as supportive. In the quantitative study, partners’ participation in treatment, Body-Mass-Index changes, and autonomy support were associated with perception of support during a weight loss study. Our results suggest that behavioral interventions should continue fostering collaboration and partners’ behavior changes. Further, they suggest that training partners to provide and communicate about autonomy supportive behaviors, in line with SDT, may also enhance obesity treatment.