The former Sonny with a Chance star was admitted to an in-patient programme in Illinois in 2010 after suffering a breakdown on tour.
In 2011, Lovato went public with her issues and spoke candidly about her eating disorder and self-mutilating problems - just months before agreeing to join Britney Spears on the hit U.S. show.
She insists she's in a great place now but admits it was definitely a risk to her health to sign on for the high-stress TV job.
She tells teen magazine Cosmo On Campus, ""I don't think I was ready when I started on The X Factor. In an ideal situation I would have maybe waited a year or more. I dived into work really quickly and maybe that wasn't the best idea at the time, but the place I am in today is so much better than I could have ever imagined, so I'm really glad.""