History & Key Figures

Cynthia Kenyon (born 1954) trained as a molecular biologist at MIT before starting her own lab at UCSF in the 1980s, initially studying developmental genetics in C.

The free radical theory of aging holds that aging results from the cumulative cellular damage caused by reactive, unstable molecules called free radicals.

Élie Metchnikoff, born Ilya Ilyich Mechnikov in 1845 in what is now Ukraine, was a zoologist and microbiologist whose early career established one of the foundations of modern immunology.

The Hayflick limit refers to the finite number of times a population of normal, non-cancerous human or animal cells can divide in laboratory culture before entering a permanent nondividing.

Before the 1940s, the biology and medicine of aging existed mainly as a scattered set of observations within physiology, pathology, and clinical medicine rather than as an organized scientific field.

Roy Lee Walford (1924 to 2004) was a professor of pathology at the UCLA School of Medicine who spent decades studying the relationship between diet, immune function.

The elixir of life was a substance, or family of substances, that Chinese alchemists and court physicians believed could grant physical immortality or vastly extended lifespan.

Aubrey de Grey (born 1963 in London) trained in computer science at Cambridge and worked in artificial intelligence before shifting to biogerontology in the early 1990s.

David Andrew Sinclair (born 1969 in Sydney, Australia) earned a biochemistry degree and a PhD in molecular genetics from the University of New South Wales before joining Leonard Guarente's.

The philosopher's stone was a substance sought by alchemists across the ancient Mediterranean, the medieval Islamic world, and medieval and early modern Europe.

The idea that mortal humans could become xian, variously translated as immortals or transcendents.

The Fountain of Youth is a legend about a spring or river whose waters restore youth to anyone who drinks or bathes in them.