[Yerba mate as a safe polyphenolic source during human lactation]. / La yerba mate como fuente segura de polifenoles durante la lactancia humana.

Background: Yerba mate intake is conditioned by assumptions about its benefits and risks for breastfeeding, with a lack of solid evidence. Objective: To evaluate the safety of yerba mate teas during human lactation. Material and methods: Cross-sectional study with 279 adult lactating women from Argentina (years 2013-2020), during the first six months postpartum, without current pregnancy or active pathologies. Social, reproductive, and food data were compiled. Body mass index and percentage of body fat were also established. The adherence to dietary patterns, intake of yerba mate and its phytochemicals were estimated. Milk biochemistry included nutritional, oxidative and tissue markers. Intake means were compared using the Wilcoxon's test depending on the data recorded, while the multiple nonparametric Kernel regression was used to evaluate the effects on body and milk. Results: It was found a wide range of intake, and tube-sipped tea was the main way of consumption. Concerning its constraints, in-cup tea was more used by women without a partner, whereas tube-sipped tea was consumed mainly by employed women, during late postpartum, and with 12 or more years of formal education. Additionally, these teas were an important source of 18 hydroxycinnamic acids and flavonoids. Moreover, yerba mate provided more than 35% of dietary polyphenols. No anthropometric effects or changes in milk nutrients and biomarkers were found. Conclusions: Yerba mate was a safe source of polyphenols, as it did not compromise lactation and maternal nutritional status.

Introducción: el consumo de yerba mate está condicionado por supuestos sobre sus beneficios y riesgos para la lactancia materna, los cuales carecen de evidencia sólida. Objetivo: evaluar la seguridad de las infusiones de yerba mate durante la lactancia. Material y métodos: estudio transversal con 279 mujeres lactantes adultas de Argentina (años 2013-2020), en los primeros seis meses postparto, sin embarazo ni patologías activas. Se recopilaron datos sociales, reproductivos y alimentarios, índice de masa corporal y porcentaje de grasa corporal. Se estimó adherencia a patrones alimentarios, consumo de mate y sus fitoquímicos. Se analizaron marcadores nutricionales, oxidativos y tisulares en leche. Por la prueba de Wilcoxon, se compararon las medias de consumo según las variables recopiladas y por regresión no paramétrica de Kernel múltiple se evaluaron los efectos corporales y lácteos. Resultados: se encontró un amplio rango en la ingesta de infusiones y el mate cebado fue la principal forma consumida. Respecto a sus condicionantes, el mate cocido fue más bebido por mujeres sin pareja, mientras que el mate cebado fue más consumido por puérperas tardías, con empleo y nivel educativo ≥ 12 años. Además, estas infusiones constituyeron una fuente relevante de 18 ácidos hidroxicinámicos y flavonoides, que proveyeron diariamente más del 35% de los polifenoles dietarios. No se encontraron efectos corporales ni cambios en los niveles de los nutrientes y en los biomarcadores lácteos. Conclusiones: la yerba mate fue una fuente polifenólica segura que no comprometió la lactancia ni el estado nutricional materno.

The Effect of Freeze-Drying on the Nutrient, Polyphenol, and Oxidant Levels of Breast Milk.

OBJECTIVES: Human milk banks need to extend the suitability of milk for breastfeeding, and for this technological advances are required. Our aim was to establish the capacity of freeze-drying to conserve milk properties without further oxidative deterioration. METHODS: One hundred sixteen healthy women participated from the city of Cordoba (Argentina). Proteins, glucose, triglycerides, polyphenols, and markers (nitrites, superoxide anion, hydroperoxides, lipoperoxides, and γ-glutamyl transpeptidase) were measured in their fresh milk. Samples were then separated for three treatments as follows: freezing and conservation for 6 months at -80°C (F: positive control); freeze-drying for 24 hours at ≤-70°C and ≤1.33 Pa and conservation for 6 months at 4°C (FD: treatment of interest); and freeze-drying for 24 hours at ≤-70°C and ≤1.33 Pa and conservation for 6 months at -80°C (FD+F). Next, analyses were repeated and compared by ANOVA and Tukey tests. RESULTS: Fresh milk showed these values per L as follows: proteins: 12.62 ± 2.51 g, glucose: 4.44 ± 0.25 g, triglycerides: 34.26 ± 0.59 g, polyphenols: 53.27 ± 8.67 mg, nitrites: 62.40 ± 19.09 mg, superoxide: 3,721.02 ± 198.80 OD, hydroperoxides: 7,343.76 ± 294.53 OD, lipoperoxides: 7,349.72 ± 398.72 OD, and γ-glutamyl transpeptidase: 4.66 ± 0.55 IU. Glucose was decreased after F treatment (p < 0.05), all variables were conserved by FD and were not improved by the FD + F combination. CONCLUSIONS: Freeze-drying achieved suitable conservation and may improve bank functioning, by protecting nutritional properties, polyphenol-related functionality, and oxidative integrity of human milk through a 1-day treatment with easy maintenance.