The Smash star admitted that she has continued to have problems following the eating disorder she had in her early 20s.
Speaking on The View, she said: "I still struggle. When I look in the mirror I [think], 'I don't know what everybody thinks is so great'."
The 27-year-old continued: ''I have an amazing relationship with food. But I wish things were a bit tighter here and there. Everywhere."
She spent three months at a Los Angeles clinic prior to taking part in American Idol in 2006.
She recently told Self: "I love my body when I'm in the best shape I can be in. It feels good to be strong."
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