"A big thanks to all of you who have been in my corner!" the actress wrote

By Michele Corriston
Updated June 15, 2015 03:50 PM
Alberto E. Rodriguez/Getty

Sasha Pieterse has a message for critics of her fuller figure.

The Pretty Little Liars actress knows her character Alison DiLaurentis has been looking different lately, and now she’s opening up about the real-life health issue that’s responsible.

“As a lot of you have noticed my body has gone through some changes, and I want to clear the air and give you an explanation. I have been facing a bad hormone imbalance that has thrown my body completely out of whack,” the 19-year-old wrote on Instagram last week. “I want to assure you that I’m healthy and getting everything back on track! A big thanks to all of you who have been in my corner!”

But the actress isn’t going to take any more body-shaming from cruel viewers.

“We live in such a judge mental society that puts every kind of flaw, including weight gain, in the same category,” she wrote. “And for those of you who are struggling with any health problem, hormone imbalance, and weight gain of any sort I urge and encourage you to please deal with it in a healthy [manner]. YOU and YOUR health are what matters, not anyone else’s opinions and assumptions of you.”

Friendly reminder to all the PLL fans out there: Pieterse is the youngest woman in the cast and landed the role at the age of 12. So yeah, she’s going to grow from season to season! Save the hate for A.

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Catch Pieterse as redeemed mean girl Ali when PLL airs Tuesdays at 8 p.m. ET on ABC Family.