12/22/2014 11:28 EST | Updated 12/22/2014 12:59 EST

Demi Lovato Responds To Fat-Shaming On Twitter With Cheeky Reply

Demi Lovato may be best-known for singing songs like "Really Don't Care," but she's also a master at standing up to online bullies.

The 22-year-old replied to a Twitter user who sent an angry tweet in her direction, telling Lovato, "Shut up fatty don't choke on ur McDonalds!" In response, the former X Factor judge wrote, "But....Big Macs...." and completed her retort with four "raise the roof" emojis. Lovato's tweet has since garnered 18,449 retweets and counting.

The singer's cheeky comeback also carries a special weight, as Lovato has revealed she continues to struggle with addiction, bulimia and self-confidence concerns.

According to an E! Online report about her January 2014 Fitness magazine cover shoot, she nearly returned to rehab to help manage her eating disorder in the summer of 2013.

Earlier this year, Lovato told Seventeen magazine that, "There have been times when I definitely have been tempted to get rid of my dinner."

"But I will deal with it for the rest of my life because it's a life-long disease," said Lovato.

In that same interview, the star discussed how she handles criticism from others — an attitude reflected in her response to the Twitter troll.

"I don't let anyone's insecurities, emotions, or opinions bother me," she said. "I know that if I am happy, that's all that matters to me."

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