Former heroin addict shares incredible transformation after years of homelessness, rehab

The man behind one of social media's most popular addiction and recovery blogs has candidly discussed his own decade-long addiction to heroin in a new interview.

'The Addict's Diary' founder Kevin Alter spent almost 12 years of his life homeless and high on class A drugs, his story eventually inspiring a blog dedicated to other people's journeys of addiction and recovery.

Now 31 and three years sober, Alter says his twenties were lost to "a syringe and a bag of heroin".

Alter told Fox News his addiction started as a 17-year-old trying cocaine for the first time with friends while growing up in New York's Long Island.

The teen relapsed shortly after his parents sent him to his first of 29 inpatient treatment centres. Alter rejoined his old group and struggled to "let go of people" who hindered his recovery.

Despite graduating high school and receiving a college scholarship, Alter couldn't resist temptation. Three days of sniffing heroin with his old friends concluded his first year of college. The fourth day, he was offered a syringe.

That first experience with heroin turned into 11 years plagued with addiction, rehab, relapse, homelessness, heartbreak and the deaths of many friends.

"It sucked," Alter told the outlet.

Alter would sober up long enough to scrape a pay cheque, coming home to a train station in Queens, New York. He eventually moved to a building stairwell in the Bronx.

"I didn't even want to get clean - put yourself in the frame of mind of going in and out of treatment for 12 years, coming from a good family... you're just this lost person... I thought I was going to be a heroin addict forever," he admitted.

Another treatment opportunity led to a stint at Alter's 29th facility. It was only there that Alter was forced to confront the reasons why he got high - a deep sense of insecurity and self-hatred he had ignored for years.

Three years later, Alter has amassed almost 570,000 followers from the popularity of 'The Addict's Diary', a venture he launched 22 months ago. Alter has labelled himself "the luckiest heroin addict alive" and has finally learned to love himself.

Alter's candid and honest approach has helped foster a sense of trust and authenticity between himself and those who share their stories on 'The Addict's Diary'. He also spends time responding to addicts who reach out to him for help and advice.

When he's not running his blog, working on his podcast or travelling to schools to talk to students about addiction, Alter is rebuilding his relationship with his relatives and making up for lost time.

"It's been a beautiful process," he told the outlet.