Defeating old age? In 1899, Elie Metchnikoff woke up in Paris to learn he had done just that. At least, that's what the newspaper headlines said. Before long he was inundated with mail from people begging him to help them live forever. The only problem? He didn't know how to do it.

At the time, Metchnikoff was one of the world's most famous scientists. And he believed aging was a disease he could cure. He dedicated his life to that quest, spending his days interviewing centenarians, pulling gray hair out of colleagues and old dogs, and boiling strawberries — all in the pursuit of eternal youth. If you've ever had yogurt for breakfast, you likely have Metchnikoff to thank. (This episode first ran as The Man Who Cured Aging)

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Guests:

Carole Haber, professor and Dean Emerita of Tulane University in the School of Liberal Arts

Jay Olshansky, professor of public health at the University of Illinois at Chicago

Luba Vikhansky, author of Immunity: How Elie Metchnikoff Changed the Course of Modern Medicine

Lina Zeldovich, science and medical journalist