The Keeping Up With The Kardashians star, 17, shared a throwback photo to Instagram alongside the caption: "Throwback to when I was 15 pounds skinnier & had a little blonde goin on."
Fans were quick to tell Kylie she looks fantastic as she currently is, with one saying: "You look a lot happier & healthier! Be you & stay real, my friend!"
The teenager joked earlier this year that the only thing keeping her in shape is having father Bruce Jenner's genes. He's an Olympic champion.
She told E!: "I eat so bad right now. I eat so many sweets and so much candy but it's the Bruce Jenner genes. I have to start working out very soon."
Kylie was pictured out and about in LA earlier this week amid rumours she could be getting her own reality show.
According to reports, the teenager and model sister Kendall Jenner, 19, have been in talks about starring their own spinoff from Keeping Up With The Kardashians, the family reality show.
E! Network, however, has said this isn't true.
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