Just days after commending fellow actress Catherine Zeta-Jones for sharing her struggle with bipolar disorder, Demi Lovato revealed she too suffers from the disorder.

The 18-year-old Disney star told PEOPLE about her diagnosis in a recent interview: "I never found out until I went into treatment that I was bipolar." Lovato spent three months in a residential center undergoing therapy for anorexia, bulimia and depression.

"Looking back it makes sense," she told PEOPLE about her diagnosis. "There were times when I was so manic, I was writing seven songs in one night and I'd be up until 5:30 in the morning."

"I feel like I am in control now where my whole life I wasn't in control," she added.