Schilling discussed details on WEEI-FM in Boston on Wednesday. The former Red Sox right-hander announced in February that he had cancer but hadn't disclosed what kind. He has said he is in remission after seven weeks of radiation and chemotherapy and has lost 75 pounds.
"I'm not going to sit up here from the pedestal and preach about chewing," he said. "It was an addictive habit. I can think about so many times in my life when it was so relaxing to just sit back and have a dip and do whatever.
"And I lost my sense of smell, my taste buds for the most part. I had gum issues, they bled, all this other stuff. None of it was enough to ever make me quit."
Schilling revealed the type of cancer two months after Hall of Fame outfielder Tony Gwynn died at the age of 54 of oral cancer, a disease he attributed to years of chewing tobacco.
Use of chewing tobacco has been "a norm in the baseball culture," Red Sox manager John Farrell said. "On the heels of the unfortunate passing of Tony Gwynn and now what Curt's going through, you would think that this would be more of a current beacon for guys to take note and know that there's a price to be paid if you're one of the unfortunate ones that is stricken by cancer."
Major League Baseball prohibits having smokeless tobacco in public view and imposes fines for violations. Minor leaguers cannot use it in games.
Former Red Sox left-hander Jon Lester was coming back from treatment for anaplastic large cell lymphoma in 2007, Farrell's first year as Boston's pitching coach. Lester, sent to Oakland at the trade deadline last month, was 4-0 that year and won the final game of Boston's four-game sweep of the Colorado Rockies in the World Series.
"Any time a public figure who is, unfortunately, diagnosed with cancer, is able to come out and speak about it — I know how hard that can be — it brings awareness," Lester said after Schilling's disclosure, "and maybe sheds a little light or a little hope on somebody who's struggling."
Before his team faced the Red Sox on Wednesday night, Los Angeles Angels manager Mike Scioscia said the use of smokeless tobacco "is non-existent in the minor leagues during a game. ... You hope that the next generation will heed the mistakes of the prior generation."
Schilling is a three-time World Series champion with the Arizona Diamondbacks and Red Sox.
"It's a very serious issue," said Baltimore Orioles manager Buck Showalter, Schilling's manager with the Diamondbacks in 2000, the year before they won the World Series after Showalter left. Awareness "has gotten a lot better over the years through things like Curt is doing, but there's a long way to go."
Schilling played from 2004-07 with the Red Sox, who won the World Series in his first and last seasons with them.
"He's elected to keep it very personal and I wouldn't want to betray that confidence," said Cleveland Indians manager Terry Francona, who managed Boston from 2004-11. "He's said what he's wanted to say, when he's wanted to say it."
Colorado Rockies outfielder Michael Cuddyer said he tries to encourage young players not to use smokeless tobacco.
"Anybody that thinks about it or wants to do it because it's cool should realize it's definitely not," he said. "You're seeing these guys' lives get put in jeopardy because of it. Young players and young kids should be aware of that. It's a disgusting habit."
Schilling is being sued by Rhode Island's economic development agency after his video game company received a $75 million state loan guarantee and then collapsed.
AP Sports Writers Pat Graham and Janie McCauley and freelancers Patrick Donnelly and Paul Ladewski contributed to this story.