Dr. Walter Bortz II didn’t quite make it to 100 years old, but his life’s work was to help countless others get as close to that milestone as they could.

“His books had a huge effect on people. So many people would say to him, or even to me, that what he’s done has changed their lives,” said Jeanne Kennedy, Bortz’s partner since 2017. “That was a wonderful thing to have.”

Bortz died in his Portola Valley home on Aug. 5 after a period of declining health, Kennedy told this news organization. He was 93 years old.

Best known for his research and published works on aging and living longer, Bortz worked as a physician at the Palo Alto Medical Foundation for decades, where he specialized in geriatrics. His books include “Dare to be 100,” “We Live Too Short and Die Too Long” and “Living Longer for Dummies,” which explore how physical exercise and other controllable factors contribute to human aging.

He also wrote 150 scientific articles for acclaimed research publications like JAMA, and articles for publications like The New York Times and The Washington Post, to name just a few.

"My mantra is '100 healthy years,'” Bortz told the Palo Alto Weekly in a 2018 interview. “Our birthright, our warranty is 100 healthy years if we don't screw it up."

Despite his best efforts, Bortz didn’t achieve the centenarian milestone he hoped for – as is always the case with health, there are some things that one can’t control, no matter how hard they try.

His partner Kennedy said that as he got older, Bortz had to give up running, one of his favorite ways to exercise, due to a neurological issue in his legs. Bortz ran 45 marathons over the course of his lifetime before his health forced him to hang up his running shoes.

“He never wanted a long death, but that’s really what he had,” Kennedy said. “On the other hand, he never talked about it, he never railed against it. He wasn’t depressed by it. He just continued to live as much as he could, and as well as he could, as long as he could.”

In addition to his community involvement through his years at the Palo Alto Medical Foundation, Bortz was known for his work as a clinical professor at the Stanford University School of Medicine.

“He was very proud of working up from being an assistant professor, to an associate professor, to a full professor of clinical medicine,” Kennedy said. “That meant a lot to him.”

In addition to his partner Kennedy, Bortz is survived by his four children, Danna, Gretchen, Edward and Walter. He’s also survived by nine grandchildren and two great-grandchildren. His wife Ruth Anne Bortz, who was also an avid long-distance runner, died in 2015.