Matt Kaeberlein

At a glance

• Matt Kaeberlein is an American biologist and biogerontologist. Formerly a professor of pathology at the University of Washington in Seattle, he is now CEO of Optispan, a company focused on healthy ageing.
• He first studied ageing in yeast and the genes and signalling pathways, such as mTOR, that influence lifespan across many species.
• He co-founded the Dog Aging Project, which follows thousands of dogs to understand ageing in real-world conditions. Its TRIAD study tests rapamycin in older dogs.
• Rapamycin, originally an immunosuppressant, consistently extends lifespan in mice. Whether the same holds in humans is not yet proven.
• Through the Optispan podcast and social media he is a critical voice against longevity hype, expensive tests without evidence and exaggerated claims.
• For longevity, he matters because he combines enthusiasm for new interventions with sobriety about the evidence.
• Takeaway: rapamycin for longevity is off-label and experimental; discuss such ideas with a doctor rather than experimenting on your own.