'Skyscraper' songstress Demi Lovato has admitted that she first felt conscious of her body at the age of 3.

The star, who is currently working as a judge on X Factor USA, sat down for a personal interview with Katie Couric and revealed that she wanted a flat stomach as a toddler after noticing how her stomach stuck out while wearing a diaper:

"I remember being 3 years old in a diaper and rubbing my hand over my stomach, and I remember thinking in my head ‘I wonder if one day this will ever be flat?’"

She added that her experience of being bullied as a child has had a significant impact on her life ever since and it was the verbal abuse that really took its toll:

"I’ve always said I wished that they had just hit me in the face and gotten it over with because what they said to me sticks to me to this day and it [turned] me into the person I am today."

When asked by Couric about the '09 incident that saw her hit one of her backing dancers in the face, Lovato explained: "I wasn’t really in control of my emotions at the time. I was just out of control and there’s no excuse for it but it definitely showed everyone I needed to get help and I think two days later I was checking into rehab."

The full interview will air on 'Katie' next Monday, September 24. Watch her discuss Niall Horan with Simon Cowell here: