She has been open about her past battles with substance abuse, self harm and an eating disorder.
And Demi Lovato celebrated six years of sobriety in an inspirational tweet to her 55.5m followers.
One fan wrote: 'So glad to hear that baby, you're such an inspiration to everybody. Love you.'
Another wrote: 'Way to go Demi. You are inspiration to not only your fans, but anybody who has ever dealt with addiction. We are rooting for you.'
Demi previously admitted that, as part of her battle against alcoholism, she's been forced to give up partying because it can trigger her cravings for drink.