"I've been working so hard to get healthy and fit," starlet Demi Lovato tweeted earlier today, along with a sexy picture of herself in a white bikini.

Lovato left the Jonas Brothers concert tour late last year to seek treatment for issues concerning her health, but she seems to be thriving today.  "I'm excited (about) how far I've come since being completely ashamed of my body," the 18-year-old singer and actress explained alongside the photo. "I can't believe I am about to do this ... Here's my bikini time body!"

Demi Lovato's photo: I've been working so hard to get healthy and fit.. I can't believe I'm about to do this but I'm so excited.. Here's my bikini time body!Related Article: Demi Lovato: "Love is Louder than the Pressure to Be Perfect"

Lovato is very active in charities involving advocating for kids rights and anti-bulllying campaigns, and she explained in a tweet, "I want any girl/guy out there who struggles with body image or confidence to know that it IS possible to find peace with yourself."  The Sonny With a Chance starlet added, "It hasn't been easy, but it starts with a commitment to yourself, your mind ... and your soul. And trust me, I'm still working at it!"

We are glad to see Demi looking healthy and happy!  What do you guys think of her cute curves?

Photo courtesy of Twitter