https://www.timesofisrael.com/breast-milk-proteins-superpowers-lead-to-breakthrough-for-new-class-of-oral-drugs/
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Both the stomach and the intestines are barriers that prevent hazards from entering the bloodstream. But breast milk proteins can get through these barriers and help transport nano-particles containing therapeutics to the baby.
"If compounds in breast milk can cross this barrier, it means breast milk contains 'keys' that enable them to do so," said Naftaly Kiros, one of Zinger's co-researchers. "What are these keys? That was what we aimed to uncover."