Singer Demi Lovato poses with the Favorite Pop Artist award at the 2012 People's Choice Awards in Los Angeles January 11, 2012. REUTERS/Danny Moloshok

Demi Lovato is convinced she was born with an eating disorder - because she's never experienced a "normal" relationship with food.

The 19-year-old admits she overate as a youngster, but after becoming the victim of bullying at school, the Disney star stopped eating regular meals.

She checked into rehab in 2010 to tackle a number of personal issues, including self-harming and her problems with food - and the singer/actress is sure the issue traces back to her formative years.

Lovato tells Britain's You magazine, "I think I was born with an eating disorder, because I've never had a relationship with food that was normal. I remember looking in the mirror with nappies on thinking, 'You're fat, change it'.

"I started overeating when I was about eight; I was a binge eater. I would bake a whole plate of cookies and eat them all. Then when I turned 12 I was bullied in school and they called me fat. I went from being an overeater to stopping eating and I lost about 30 pounds. From then on I continued undereating, but my weight plateaued. I started throwing up to lose weight."

Lovato is convinced she will always experience "temptation" to skip meals, but credits her eating routine in rehab with helping her address her food issues.

She adds, "Breakfast would be at 8.30am, a bowl of cereal with yoghurt or milk and fruit. Lunch would be a sandwich, salad and fruit or vegetables. Dinner might be macaroni cheese with a side of vegetables and milk.

"I cried often because I was terrified at having to eat three meals a day. I said, 'No, this is too much food.' I started eating just so that I could go home. I don't know what made it click but I realised I just wanted out of my eating disorder.

"Now I can eat as many meals as I am supposed to and not throw up any more. There's definitely temptation - every meal I fight it. It's an addiction and I'm going to have to fight it for the rest of my life. There's no cure and I may mess up, but I want to be a better role model for my fans and my younger sister."