In the 1990s, scientist Ivan Casas traveled to the Peruvian Andes in search of human microbes. Casas was head of research for a Swedish probiotics company called BioGaia. He believed that mammals, including people, passed beneficial microbes to their young via breast milk. But he’d been unable to isolate one species he thought should be there (Lactobacillus reuteri) in breast milk from women in the US or urban areas elsewhere in the world.
So he headed to the poor, indigenous communities of the Peruvian Andes, where he thought people lived a more natural life. And when he analyzed a sample collected there, sure enough, he found a unique reuteri strain.
Dr. Casas has since died. But L. reuteri proctectis, a descendant of the microbe originally isolated from a Peruvian woman’s breast milk, lives on, sold as a probiotic supplement and included in some Nestlé infant formulas. Its origin story—a microbe isolated from the breast milk of a woman living far away from the corrupting influence of modernity—is touted as part of its appeal.
Read the story at Quartz
