Rep. Tim Ryan (D) is a five-term incumbent from the heartland. His Ohio district includes Youngstown and Warren and part of Akron and smaller places. He’s 38, Catholic, single. He was a star quarterback in high school. He lives a few houses down from his childhood home in Niles. He’s won three of his five elections with about 75 percent of the vote.

So when he starts talking about his life-changing moment after the 2008 race, you’re not expecting him to lean forward at the lunch table and tell you, with great sincerity, that this little story of American politics is about (a) a raisin and (b) nothing else.

“You hold this one raisin right up to your mouth, but you don’t put it in, and after a moment your mouth starts to water,” he says, describing an exercise during a five-day retreat into the meditative technique of mindfulness, developed from centuries of Buddhist practice. “The teaching point is that your body responds to things outside of it, that there’s a mind-body connection. It links to how we take on situations and how this results in a great deal of stress.”

For Ryan, the raisin was the beginning of a transformation. The retreat, conducted by Jon Kabat-Zinn, founder of the Stress Reduction Clinic at the University of Massachusetts Medical School, led Ryan on a search into how the practice of mindfulness — sitting in silence, losing oneself in the present moment — could be a tonic for what ails the body politic.

In “A Mindful Nation,” published last week, Ryan details his travels across the country, to schools and companies and research facilities, documenting how mindfulness is relieving stress, improving performance and showing potential to reduce health-care costs. It is a prescription, he says, that can help the nation better deal with the constant barrage of information that the Internet age delivers.

“I think when you realize that U.S. Marines are using this that it’s already in the mainstream of our culture,” he says. “It’s a real technique that has real usefulness that has been scientifically documented. . . . Why wouldn’t we have this as part of our health-care program to prevent high levels of stress that cause heart disease and ulcers and Type 2 diabetes and everything else?”

In the book, Ryan meets with the parents of a young soldier who committed suicide. He talks with Richard Davidson, director of the Lab for Affective Neuroscience at the University of Wisconsin at Madison, who has studied the effects of mindfulness on brain development. And he meets with Goldie Hawn, who established a foundation that teaches meditative practices to schoolchildren.

Ryan meditates in a half-lotus position for about 40 minutes each day, he says, sitting on his couch at home or on a cushion. He is optimistic about things. People are “fundamentally good,” he writes in the book. “Our basic nature is not unadulterated self-indulgence and consumption. Our spirit is not violent. Our soul does not desire that we get rich by any means necessary.”

Among other committee assignments, he serves with Rep. John Sullivan (R-Okla.) as a co-chairman of the House Addiction, Treatment and Recovery Caucus. Sullivan says Ryan’s work on meditation has aided the caucus’s mission.

“Tim brings a lot to our work on mental health, with addiction and recovery, with his focus on mindfulness,” Sullivan says. “It adds to the cutting-edge brain research that’s now developing on how to treat addiction.”

At the moment, Ryan is stumping for book sales and the message, not for votes. In Washington, he’ll speak Wednesday at the River Road Unitarian Universalist Congregation in Bethesda.

Back home, he’s got a gig scheduled for early summer at the Congregation Ohev Tzedek in a suburb of Youngstown. Rabbi Josh Jacobs-Velde says the four-hour event will feature Ryan and others teaching, talking and practicing mindfulness. (A potluck dinner follows, of course.)

“Youngstown, Ohio, is not the center of mindfulness training in the country,” Jacobs-Velde says, laughing. “But we’re hoping to raise some awareness of the benefits of just stopping and allowing your mind to settle. It’s really transformative. . . . That a congressman from Youngstown is doing this is wonderful.”