He hasn't had a cigarette in almost a year, first lady Michelle Obama said Tuesday.
Asked whether he had conquered a nicotine habit he picked up as a teenager, she said: "Yes, he has. It's been almost a year." Mrs. Obama offered no details on exactly when or how he did it.
She said her husband received encouragement from friends and pressure from family to stop.
"From all of the women in my husband's life, we want him to be healthy. He's worked hard at it," Mrs. Obama said during an interview Wednesday on NBC's "Today Show."
But is his relationship with nicotine really over?
About 46 million people, or one in five adults, smoke, and brain research shows that nicotine is powerfully addictive. Three-fourths of smokers who try to stop fall off the wagon within six months, according to the National Institute on Drug Abuse. Smokers will tell you it often takes repeated attempts to quit long term.
Obama, who has one of the world's most stressful jobs and recently has been grappling with political instability in Egypt, a close U.S. ally, has walked this tobacco road before. He announced in February 2008, during his presidential campaign, that he was quitting smoking - again.
"He's always wanted to stop," Mrs. Obama said Tuesday. She said he wants to be able to look daughters Malia, 12, and Sasha, 9, in the eye and deny that he smokes should they ask.
The issue of Obama's smoking last surfaced in December, when White House press secretary Robert Gibbs was asked about it and said he had "not seen or witnessed evidence of any smoking in probably nine months." That timeline would put Obama's final cigarette puffs in March of last year.
At the time, Gibbs stopped short of asserting that Obama had quit completely.
The White House offered no details Tuesday, in keeping with its practice of trying to keep Obama's habit out of the spotlight.
Obama last addressed the question in June 2009. Before signing a tough anti-smoking law designed to keep millions of teens from getting hooked, Obama ruefully admitted that he had spent his adult life trying to give up cigarettes.
At a news conference the following day he copped to sneaking an occasional puff.
"I constantly struggle with it," the president said. "Have I fallen off the wagon sometimes? Yes. Am I a daily smoker, a constant smoker? No."
Obama said he didn't smoke in front of his kids or other family and had declared himself "95 percent cured." But he also acknowledged times "where I mess up."
"Once you've gone down this path, then it's something you continually struggle with," he said.
Obama has said that he used to light up about five times a day but that stress sometimes drove him to smoke more often. He promised his wife he'd quit if she agreed he should run for president.
"I hate it," Michelle Obama told CBS' "60 Minutes" early in the campaign. "That's why he doesn't do it anymore, I'm proud to say. I outed him - I'm the one who outed him on the smoking."
She said one of her requirements for entering the race was that "he couldn't be a smoking president."
Based on her comments Tuesday, he is no longer that.
The first lady said she was proud of her husband but had not pressed for details. "When somebody's doing the right thing I don't mess with them," Mrs. Obama said.
Obama has used nicotine gum in his quest to quit smoking. "I've been chewing Nicorette strenuously," he said in 2007. The White House physician urged him last year to continue his "smoking cessation efforts" - the use of nicotine gum.
During the presidential campaign, aides filled their pockets with the gum to help Obama control his urges. He occasionally bummed cigarettes from staff, while making sure to emphasize that he was trying to quit for good.
U.S. smoking rates have dropped dramatically since 1964, when the first surgeon general's report declared tobacco deadly, but progress has stalled in the past decade. The government had hoped to push the rate to 12 percent by last year, but the goal has been missed and pushed off to 2020.
Gibbs said Tuesday that a few White House aides, including trip director Marvin Nicholson, also had quit smoking. He suggested the president may have benefited from that, too.
"When somebody decides to quit smoking, to try to overcome the physical addiction that they have, they do it not just because they want to but because others want them to and because others around them give them the type of encouragement that they need to break what is, what is a tough habit to break," Gibbs said during his regular media briefing after being told of the first lady's comments.
Associated Press writers Ben Feller, Julie Pace and Erica Werner and Medical Writer Lauran Neergaard contributed to this report.