High-polyphenol Pre-Hispanic Diet from Pre-Gestation to Lactation Modulates Maternal Physiology, Milk Composition, and Offspring Outcomes in Wistar Rats.

BACKGROUND: Maternal nutrition during pre-gestation, gestation, and lactation plays a central role in early-life programming, according to the Developmental Origins of Health and Disease (DOHaD) framework. However, evidence regarding bioactive-rich traditional diets under physiological conditions remains limited. OBJECTIVE: To evaluate the effects of a high-polyphenol Pre-Hispanic dietary pattern on maternal metabolism, mammary gland differentiation, milk composition, and offspring nutrient exposure in a non-obesogenic rat model. METHODS: Sixteen female Wistar rats were randomized to either a control diet (AIN-93G) or a Pre-Hispanic diet containing nixtamalized white maize, black beans, Serrano chili peppers, and red tomatoes. Diets were administered from pre-gestation through lactation. Maternal metabolic markers, mammary gland morphology, milk yield and composition, and offspring milk intake were assessed. Total phenolic content and selected compounds were quantified in the ingredients and diets. RESULTS: Compared with the Control group, the Pre-Hispanic group had lower serum insulin and HOMA-IR levels, indicating improved insulin sensitivity, without affecting body weight or food intake. Mammary gland weight and parenchymal area increased, whereas adipose tissue area decreased, suggesting enhanced structural differentiation. Milk macronutrient composition remained similar between both groups; however, milk from the Pre-Hispanic group showed higher early-lactation polyphenol content, lower arachidonic acid levels, and a reduced AA/DHA+EPA ratio. Offspring milk intake increased during lactation, with a trend toward higher DHA and EPA intake in the Pre-Hispanic group. CONCLUSIONS: A high-polyphenol Pre-Hispanic dietary pattern improved maternal metabolic efficiency, promoted mammary gland differentiation, and favorably modified milk bioactive composition under physiological conditions, supporting its potential role in beneficial early-life programming.