It’s Hard to Quit Zyn. The Reddit Bros Can Help.

“I threw a Zyn in as he was saying that,” Mr. Robertson said. “I was like, ‘Cool, don’t care.’”

He was not persuaded to quit until later that night when he came across a post in the Reddit group from another heavy Zyn user who described similar symptoms. He reached out to the person, and the two began to talk, said Mr. Robertson, who has now gone three months without Zyn.

The post had been written by Don Hood, 41, one of the three volunteer moderators whom Mr. McHugh enlisted in the last year to help. Mr. Hood spends hours each week outside his job as a property manager in North Carolina checking in with strangers from the group via direct messages, texts and sometimes phone calls.

Mr. Hood said he had assumed a “fatherly” role with the group’s many men in their 20s.

“I give the younger ones some hell, and some tough love,” said Mr. Hood, who quit Zyn about a year ago. In real life, he added, “you don’t sit there and talk about your problems with other guys, especially with something everyone else is using.”

Sometimes the encouragement of the group, along with repeated follow-up messages from Mr. Hood, are enough to help a young person overcome the social pressure and physical pull of nicotine. But not always. Mr. Hood sounded a little defeated when he brought up an 18-year-old who had quit for a week or so after experiencing heart palpitations.

“Everyone around him is using them, so he’s using them again,” Mr. Hood said.

Life After Zyn

No matter how many supportive messages they exchange with other anonymous Redditors, those who quit Zyn still have to navigate more treacherous territory where they cannot hide behind a username: real life.

Devon Verro, 26, an optician in Denver, is wrestling with the fact that while she has quit Zyn, most of her family members remain addicted to nicotine. When she visited her father last month, he made a “sweet” but not entirely successful effort to hide his Zyns and cigarettes before she arrived.