Music legend George Michael’s sudden death at the age of 53 has his grieving fans searching for answers and questioning whether his wild lifestyle contributed to his ill health.

Michael died in his sleep of heart failure on Christmas Day, ending an impressive 35-year career, but also a private life plagued by substance abuse, brushes with the law and self-esteem struggles.

Although he had admitted to taking drugs, Michael last year denied “highly inaccurate” reports he was an addict. His premature death has many questioning whether illicit substances played a role.

Heightening speculation, British newspaper The Telegraph quoted an unidentified source on Tuesday who claimed Michael “used heroin”.

Another UK newspaper, The Sun, quoted Michael’s friend, publicist Gary Farrow, as saying: “I believe easy access to drugs was the cause of his problems. I thought George was too bright to get involved with illegal substances. But once this disease gets hold of you, it’s hard to fight it.”

Cardiac arrest – Michael’s official cause of death according to his agent Michael Lippman –- can be triggered by cocaine, heroin or heavy drinking. The New Daily attempted to contact the deceased star’s management for comment.

Michael previously admitted to using crack cocaine and cannabis, but was never charged with heroin possession or use.

To my lovelies, do not believe this rubbish in the papers today by someone I don't know anymore and haven't seen for nearly 18 years…

— George Michael (@GeorgeMichael) July 12, 2015

In July 2015, a spokesperson for the former Wham! member responded to reports Michael had checked into rehab in Switzerland to battle crack cocaine addiction.

“Whilst it is our general policy not to comment on private matters, we would in this instance note that these highly inaccurate stories have been apparently provided to the press by the wife of a very distant family member, neither of whom has had any dealings with him for many many years,” the spokesperson said at the time.

In a 2009 interview with The Guardian, Michael admitted to smoking “seven or eight” joints a day and to “smoking crack” on an occasion in 2008, when he was arrested in a London toilet for possession of class A drugs.

He also spoke openly about abusing sleeping pills, which he claimed led to him losing his license in 2007, when he plead guilty to driving while unfit through drugs.

“I always preface this with, ‘I deserved to lose my licence, I needed to lose my licence,'” he told The Guardian.

“I had a problem with sleeping pills for about a year and a half, and I f****d up really badly. I got in the car twice when I’d forgotten I’d already downed something to try to get me to sleep.

“It doesn’t matter that it wasn’t deliberate – ultimately, I did it a second time, and I could have killed somebody. But the fact remains I was never accused of driving under the influence. I got done for exhaustion and sleeping pills.”

Michael battled depression for most of his life, after losing his first love, designer Anselmo Feleppa, to AIDS in 1993 and his beloved mother four years later. 

“I struggled with huge depression after my mother died,” he told The Independent.

“Losing your mother and your lover in the space of three years is a tough one.”

A 2010 car crash while under the influence of marijuana and a 2011 hospitalisation for pneumonia prompted many to worry about his health.

In 2013, Michael was airlifted to hospital with a head injury after falling from a car on a motorway in England and in 2014 he was rushed to hospital after collapsing at his London home.

However, in recent years Michael had been laying low. His last public performance was in 2012 and in February this year he shut down reports he was planning a comeback tour.

The last known photos of the singer, taken in September when he was dining with friends at a restaurant in Oxfordshire, England, show a man who is virtually unrecognisable from the tanned, lithe, leather jacket-clad performer who dominated the airwaves in the late 80s.

The Daily Mail reported Michael, a “perfectionist”, had become self-conscious about his weight gain, prompting him to become reclusive in his final years.

Neighbours said his appearances outside of his house had become less and less frequent, while a friend was quoted as saying they thought Michael was “a goner several times”.

Music producer Nile Rodgers took to Twitter to express his shock at news of Michael’s death, revealing he’d visited Michael’s house on December 23.

I was just at his home the morning of our last @CHICorg show on Dec 23rd in London. I'm stunned #RIPGeorgeMichael My heartfelt condolences.

— Nile Rodgers (@nilerodgers) December 26, 2016

Asked if the star had seemed ill, Rodgers responded: “I didn’t see him, I was working with his team on a project at his home.”

The project in question is believed to be a documentary about Michael’s life entitled Freedom – a film that, if it’s released as expected in March 2017, may hopefully shed more light on the pop icon’s final years.

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