RESUMEN
BACKGROUND: Racial and ethnic disparities in infant-feeding practices may negatively influence diet quality and health. OBJECTIVES: This study investigated the racial, ethnic, and language (English or Spanish) differences in infant diet quality, later diet quality, and weight status at 2-5 y, and whether these differences were explained through infant diet quality among participants in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). METHODS: Using the WIC Infant and Toddler Feeding Practices Study-2 (unweighted n = 2663; weighted n = 362,712), relationships between the Infant Dietary Quality Index (IDQI; range 0-1) and Healthy Eating Index-2020 (HEI-2020; range 0-100) and BMI z-score (BMIz) at 2-5 y were analyzed by race, ethnicity, and language preference [Hispanic Spanish-speaking, Hispanic English-speaking, non-Hispanic (NH) White, and NH Black participants]. Statistical interaction between IDQI and each group was evaluated in multivariable models. The mediation of each group through the IDQI was assessed using causal mediation methods. RESULTS: Differences in IDQI [mean (standard deviation)] were observed between Hispanic Spanish-speaking participants [0.41 (0.10)], Hispanic English-speaking participants [0.37 (0.10)], NH White participants [0.36 (0.10)], and NH Black participants [0.35 (0.09)], P < 0.001. Differences in HEI-2020 occurred at 2-5 y, with the Hispanic Spanish-speaking participants having consistently higher HEI-2020 scores. Differences in BMIz were observed at 5 y, with higher scores among Hispanic Spanish-speaking participants. Interaction between race, ethnicity, and IDQI was observed for all outcomes except for BMIz at 3 y. Through mediation, IDQI explained 13%-20% of the difference in HEI-2020 scores between Hispanic Spanish-speaking and NH White participants at 2-5 y. IDQI explained 22%-25% of the difference in HEI-2020 scores between the Hispanic Spanish-speaking and NH Black participants at 4 y and 5 y. CONCLUSIONS: Higher infant diet quality scores observed in Hispanic Spanish-speaking participants explain some of the racial and ethnic differences observed in later diet quality, suggesting that improving infant diet quality may help reduce diet disparities during early childhood.
