Study Probes Racial Disparity in Weight Loss Among Women in Internet-Delivered Behavioral Weight Loss Intervention

Monday, March 5, 2018
The Cook Center

DURHAM, N.C. – Racialized weight loss disparities may be addressed through improved engagement with Internet-delivered behavioral weight loss interventions and the adoption of weight control behaviors according to a new study co-authored by a researcher with the Samuel DuBois Cook Center on Social Equity at Duke University.

Nearly two-thirds of adults in the United States are overweight or obese (68.8%). Among racial/ethnic subgroups, African American women are the most affected by overweight/obesity. Unhealthy weight increases the risk of developing type 2 diabetes, cardiovascular disease, and some cancers, indicating an urgent need for solutions.

There has been little conclusive research into reasons for the weight loss disparity between African American and non-Hispanic White women, with African American women consistently losing 2-3 kg less weight in behavioral weight loss interventions compared to compared with non-Hispanic White women. The study shows that Internet-delivered behavioral weight loss intervention was less effective for African American women compared with non-Hispanic White women.

The article, “Racial Differences in Weight Loss Mediated by Engagement and Behavior Change,” was published in the February issue of the journal Ethnicity & Disease.

The researchers conducted a secondary data analysis of a randomized controlled trial using behavioral weight loss interventions to examine the impact of race on women’s weight loss and weight-related behaviors. The study was restricted to participants with at least weekly Internet access who were able to attend 4-monthly group sessions delivered in large or small groups. The Internet component included automated tailored feedback, self-monitoring tools, written lessons, video resources, problem solving, exercise action planning tools, and social support through message boards.

Within the sample of 170 participants, researchers found non-Hispanic White women lost more weight than African American women. Greater website log-ins and higher change in Eating Behavior Inventory score in non-Hispanic White women partially mediated the race-weight loss relationship.

“Results from this study suggest that a predominantly Internet-delivered behavioral weight loss intervention was less effective for African American compared with non-Hispanic [white] women.” they wrote.

Dr. Blackman Carr observes, “African American women experience a dual disparity in weight - burdened with the highest prevalence of unhealthy weight in the United States, and for whom gold standard behavioral weight loss treatment consistently produces lower weight loss than white women. The evidence in weight control studies including African American women clearly demonstrates this long-standing weight loss disparity. This study adds context to the dual disparity, and may guide future interventions towards equity in weight-loss treatment.”

In light of a considerable knowledge-gap with regard to the reasons for behavioral weight loss disparity, the researchers propose qualitative methods to complement this quantitative investigation in order to provide a deeper understanding of the processes that impact weight loss.

For example, researchers posit a mixed methods approach may inform which behaviors and how weight-control behaviors are differentially adopted by African American and non-Hispanic White women in a behavioral weight loss intervention. The researchers further suggest culturally sensitive behavioral weight loss intervention approaches may address race-gender-based stress. The persistence of this outcome disparity signals that more research is needed to understand the contexts and mechanisms behind weight loss in African American women.

A postdoctoral associate with the Samuel DuBois Cook Center on Social Equity at Duke University, the study’s first author, Loneke T. Blackman Carr, serves as a core member of the Cook Center’s Health Equity Working Group. The Health Equity Working Group uses an interdisciplinary approach to move beyond the acknowledgement of disparities to understand the root causes of both positive and negative health outcomes to inform practitioners, researchers and community health organizers on strength-based approaches to health. In her research and work, Dr. Blackman Carr gives particular attention to understanding and reducing the disparity in behavioral weight-loss intervention outcomes where, on average, African American women experience subpar weight loss in an effort to gain equity in public health solutions for all participants and inform policies that impact individuals’ lives.

Funding for this study was provided by the University Cancer Research Fund at the University of North Carolina at Chapel Hill.

CITATION: Blackman Carr, LT, et al. "Racial Differences in Weight Loss Mediated by Engagement and Behavior Change." Ethnicity & disease 28.1 (2018): 43-48. DOI: 10.18865/ed.28.1.43

Read the full article here.