Effects of Ilex Paraguariensis Polyphenols on Magnesium Absortion and Iron Bioavailability: Preliminary Study

Yerba maté (Ilex paraguariensis) is a native plant of South America widely consumed as hot infusion. It is a vegetable that has many bioactive compounds, such as caffeine, theobromine theophylline and saponins, phenolic compounds, mainly chlorogenic acids and dicaffeoylquinic acids, and minerals as Fe, Ca, K y Mg, which have many beneficial properties for the health. Polyphenols have the property of chelating the transition metals, as iron and magnesium, decreasing their bioavailability. Iron deficiency anaemia and subclinical hypomagnesemia is observed in the American population. Women at childbearing age belong to a specially vulnerable group. The aim of this work was to evaluate the "in vivo" effect of the polyphenols from yerba maté infusions, consumed in their traditional form, on the bioavailability of Fe and Mg in the diet. Eleven healhty young female volunteers participated in the magnesium and iron study. After the first blood sample was taken (time 0), the volunteers ingested 300 mL of yerba maté infusions, ferrous sulfate or yerba maté infusions plus ferrous sulfate at50 °C in no more than 5 minutes. They remained seated at a comfortable temperature throughout the study. Blood samples were taken 20, 40, 50, 60, 80, 100 and 120 minutes after ingestion.The yerba maté infusions prepared in their traditional form of “hot maté”, which containining an average of 4.68 ± 0.54 GAE/L of polyphenols, have an inhibitory effect on the bioavailability of the magnesium and mainly on non-heminic Fe consumed as ferrous sulphate of the 76 ± 10 % .