Robbie Williams feared he was "going to die" if he didn't "take action" and change his eating habits and lifestyle.
The 'I Love My Life' hitmaker - who is an ambassador for global wellness company WW - has battled with his weight for many years, used to have a 40-a-day cigarette habit and previously entered rehab for an addiction to prescription drugs.
Robbie has long kicked his past habits in the head and now follows a health and fitness plan after joining WW - formerly Weight Watchers - but has admitted if he had kept going the way he was he believes he would have ended up dead.
Speaking on the latest episode of WW's 'Wellness That Works' podcast, he said: "I knew I had to take action or I was going to die.
"Take it in small steps.
"You can only get bucked off the horse so many times, daily, secondly, minutely, but you just keep getting back on the horse and then your percentage of who you are, where you are and how you feel about yourself and life will get better and better but it's a hard journey."
Being able to speak up about how he was feeling has been vital for the 45-year-old singer - who has children Teddy, six, Charlie, four, and 13-month-old Coco with wife Ayda Field - and he's so "happy" that talking about mental health is no longer taboo because it's vital to getting well.
He said: "We have come on leaps and bounds with how the public perceive what's going on with mental health.
"It's a much healthier place to be.
"People are very open and talking about what's going on for them and their minds, and their mental health.
"It's basically the start of the process of talking about this stuff, and I'm very proud and happy to be in a society that is now getting to grips with what this is."
Listen to the episode in full and subscribe to WW's new podcast, Wellness That Works on iTunes, Spotify & YouTube.
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