"I am a size six, I'm proud of what I am," she says as a guest on Friday's episode of The Real. "This woman said that I was fat. And I'm like, wow, the average size in America is a size 12/14, and so I guess you're calling a lot of women fat, which I think is really ridiculous."
The Tia Mowry At Home star, 37, decided to share a screenshot of her bully's comment on her Instagram page.
"People have to be responsible for their actions," she explains. "I have to be responsible for what I do and what I say on Instagram, but not only that, it's about social media bullying. […] This is a huge problem."
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"Everyday!" she says. "I don't know how I survived it."
Mowry-Hardrict says she hopes for an end to this type of destructive behavior.
"Why are we doing this to each other?" she says. "We need to support each other. I think that women are beautiful at any size that they are."
The Real airs weekdays (2 p.m. ET) on Fox.