Defense Date
2026
Document Type
Dissertation
Degree Name
Doctor of Philosophy
Department
Epidemiology
First Advisor
Chrisa Arcan
Second Advisor
Elizabeth Prom-Wormley
Third Advisor
Marshall Brooks
Fourth Advisor
Niloofar Ramezani
Fifth Advisor
James Hebert
Abstract
Background and Objectives: Immigrants in the United States undergo acculturation — a process of sociocultural and behavioral adaptation to the host country. Increasingly, behavioral adaptations have been associated with cardiometabolic health and chronic disease risk. Metabolic syndrome (MetS), a cluster of conditions including abdominal obesity, elevated blood pressure, impaired fasting glucose, elevated triglycerides, and reduced HDL cholesterol, is a major risk factor for type 2 diabetes mellitus, cardiovascular diseases and other chronic diseases, including cancer. Despite the growing immigrant population in the U.S., the role of diet and dietary acculturation in MetS development remains poorly understood in this population. This dissertation, through Studies 1 and 2, investigated the contribution of diet to MetS among adult immigrants using quantitative methods of assessment, while accounting for acculturation. Using qualitatively methods Study 3 explored potential factors contributing to the acculturative transition among West African immigrants.
Methods: Studies 1 and 2 used NHANES data (2005–2018). Study 1 (n=10,039) identified nutrient-based dietary patterns through an exploratory factor analysis (EFA) and a confirmatory factor analysis (CFA) and examined associations with MetS via survey-weighted logistic regression. Study 2 (n=4,863) examined whether the energy-adjusted Dietary Inflammation Index (E-DII) mediated, moderated, or confounded the acculturation–MetS relationship using linear regression. Study 3 used six focus group interviews and a member checking with 19 first generation West African immigrant adults in the U.S. to explore dietary acculturation experiences including: dietary changes, drivers of change, community-related factors, and other related experiences.
Results: Study 1: Of the total participants (mean age 44 years, 49.9% female), 30% had 3 or more MetS criteria. Three dietary patterns were identified — Western/Energy-Dense, Animal/Dairy, and Plant-Based. Greater adherence to the Plant-Based pattern was associated with lower odds of MetS. Study 2: Of the participants (mean age 44 years, 50% female), 29% had 3 or more MetS criteria. Acculturation was positively associated with MetS and with a more pro-inflammatory diet; however, E-DII did not mediate, moderate, or confound the acculturation–MetS relationship. Study 3: The focus group participants included 11 female and 9 male (mean age of 34 years). They expressed a strong desire to maintain traditional diets but faced structural barriers, including food cost, limited access to desired ingredients, and time constraints around acquiring and preparing food.
Conclusions: A plant-based dietary pattern appeared capable of preventing the development of MetS among immigrants. Dietary Inflammatory Index and acculturation were independently associated with MetS among immigrants in the U.S., indicating that acculturation may be associated with higher MetS risk by mechanisms beyond dietary inflammation. This suggests the need to investigate additional psychosocial and behavioral pathways. Additionally, the use of a more culturally representative dietary acculturation scale may provide a more comprehensive understanding of the relationship between acculturation, E-DII, and MetS. Culturally tailored interventions around healthy eating are necessary for reducing cardiometabolic disparities in this population.
Rights
© The Author
Is Part Of
VCU University Archives
Is Part Of
VCU Theses and Dissertations
Date of Submission
5-6-2026