When journalist Bill Gifford turned 40, his friends gave him a cake shaped as a tombstone with the words, "R.I.P, My Youth." As he reflected on his creeping memory lapses and the weight he'd gained, Gifford got interested in the timeless quest to turn back the aging clock or at least slow it down.

His latest book, Spring Chicken, explores everything from some wacky pseudo-cures for aging to fascinating research that point to causes of aging at the cellular level.

"In high school biology we pretty much learn that cells divide and divide forever and that's kind of what they thought up until about 1960," Gifford tells Fresh Air's Dave Davies. "Now they know that cells actually have a kind of lifespan they have a limit to the number of times that they can divide."

Gifford says that after they're done dividing, the cells go into a state called "replicative senescence."

"So they go from being these lively dividing cells to basically retiring," he says. "And they're sitting there and they're kind of grumpy."

Scientists have learned that these cells are "basically toxic," he says.

"It's sort of like certain people bring everybody down," Gifford says. "Senescence cells are kind of the same way. Some people think that senescence cells actually drive much of what we recognize as aging."

Gifford's book not only explores the research at the cellular level, but he also looks at the history of anti-aging, how exercise, diet and stress affect growing old and interesting phenomena in the natural world like the naked mole rat. It lives long, shows no increase in mortality with age, never gets cancer and never experiences menopause.

"They live underground; they're from Africa and they live in a colony," Gifford says. "I held one in my hand and she was the size of between a mouse and a rat and she was 28 years old, whereas a mouse lives to about two years old. In human terms, it was like a 600-year-old person ... and she was pregnant."

These animals, Gifford says, have repair mechanisms in their cells that allow the cells to survive damage and live longer.

Continue reading here:
From Naked Mole Rats To Dog Testicles: A Writer Explores The Longevity Quest