Degree of Food Processing is Associated with Glycemic Control in African American Adults with Type 2 Diabetes: Findings from the TX STRIDE Clinical Trial.

ABSTRACT

BACKGROUND: Type 2 diabetes mellitus (T2DM) disproportionately affects African American (AA) populations. Despite the importance of diet in diabetes management, the association of diet quality and/or the degree of food processing with glycemic control in AA adults with T2DM remains unclear. OBJECTIVE: This study aimed to examine associations between diet quality scores and the degree of processing in the diet with HbA1c in AA adults with T2DM. DESIGN: This cross-sectional study used baseline data from participants in TX STRIDE (Texas Strength Through Resilience in Diabetes Education), an ongoing clinical trial. PARTICIPANTS/SETTING: Participants involved in this analysis (n=273) were AA adults with T2DM recruited through local churches in Austin, TX, and the surrounding areas from August 2020 through April 2023. MAIN OUTCOME MEASURES: Participants provided two 24-hour dietary recalls (one weekend and one weekday) and a blood sample to measure HbA1c. Healthy Eating Index-2015, Alternate Healthy Eating Index-2010, and Alternate Mediterranean Diet scores were calculated. The NOVA method was used to calculate the percentage of grams and calories that came from ultra-processed foods (UPF) and unprocessed or minimally processed foods (U/MPF). STATISTICAL ANALYSES PERFORMED Linear regression and ANOVA models tested associations between the diet quality scores and degree of food processing with HbA1c, adjusting for demographic covariates. Models were stratified by insulin use after finding a significant interaction with UPF and U/MPF. RESULTS: Regression analyses revealed that the percentage of grams in the total diet from UPF was positively associated with HbA1c (ßadj =0.015, Padj =0.032) while U/MPF was inversely associated with HbA1c (ßadj = -0.014, Padj =0.043). There was no significant association between any diet quality score and HbA1c. CONCLUSIONS: In AA adults with T2DM, only the degree of food processing was associated with HbA1c. Future research should explore whether a causal relationship exists between food processing and HbA1c and investigate mechanisms by which UPFs may affect glycemic control.