A new study is changing long-held beliefs about what it means to age and age well.

Researchers drew upon data from an eight-decade long study at Stanford University to learn who lives the longest and why.

Dr. Leslie Martin presents these findings in her new book, “The Longevity Project.”

In it, she debunks myths about aging and says she was surprised by a lot of their findings.

The study was launched in 1921 by a researcher who wanted to see what happened to “smart kids” as they grew into adulthood. Along the way, different researchers would revisit the group of 1,500+ study participants and interview them every five years.

Dr. Martin and her colleagues picked up the study in 1990 to look into health outcomes and longevity, which were not the original goals of the study. But she says they knew they had a gift in a such a large group of people who’d been studied for so long.

She explains some of the conventional wisdoms about aging that they’ve found to be untrue (for example, can you work yourself to death? Can worrying actually be good for you?).

Plus, find out why marriage appears to be more beneficial to men than women and how divorce seems to have a lifelong impact on children.

And Dr. Martin tells you the things you can start doing right now that can help you live not only a longer life but a richer one, too.