The 'Skyscraper' singer, who has admitted to battling an eating disorder in the past, took to her Twitter account after the MTV Video Music Awards to address people who criticised her figure at the event.
During an appearance on ABC's Good Morning America today, the teenager was praised by Robin Roberts for standing up to bullies online.
> Demi Lovato 'hoped Skyscraper honesty inspired people'
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"I think a part of it is the fact I'm Irish, Sicilian and Hispanic and I'm a little feisty!" responded Lovato, who also performed on the show.
"I just saw a bunch of comments on Twitter and I wouldn't put up with it because it's a bigger issue. It's not just about me, it's all of the young girls. What? I'm supposed to succumb to your ideal image of what thin is?
"I'm going to stand above that and be who I am and be a role model."
Lovato also spoke about her single 'Skyscraper', which shot to the top of the iTunes chart on its release earlier this year.
"I wanted to come out with a song that explained my journey rather than coming out with a dance song that wouldn't say anything to my fans," she told Roberts. "This song inspires my fans and I'm proud of that."
'Skyscraper' is the first single taken from Lovato's third studio album Unbroken, which is available from midnight tonight.
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Watch more of Demi Lovato talking to Robin Roberts on ABC below: