Tyler Oakley is one of the funniest guys on YouTube. Whether he's joking about how to stalk One Direction or throwing the slumber party of our dreams, his humor is a big part of why he racks up millions of views. But now, he's opening up for the first time about something serious: his struggles with an eating disorder.

Related: Celebrities who went public with their eating disorder

“Talking about it is really hard because it’s something I suppress and work through every day," he tells Seventeen magazine. "And I haven’t really talked about body image in videos. I assume when people read this, they’ll be like, ‘Oh, you’re not fat.’ That’s not what it’s about at all. Even when I was the skinniest I’d ever been, I was still not happy.” 

Related: Andie Mitchell: 'Thinness doesn't equal happiness'

Oakley is the cover star of the teen magazine's October issue. "With videos, meet and greets, and a million pictures a day, it's definitely a thing that I think about," he says in the cover story. "It's not about clothes fitting. It's not about feeling chubbier than normal. I'd beat myself up over a day that I'm not active. If I'm lazy, then I feel grody."

Oakley has a book coming out next month called "Binge," and in it, he makes another startling confession: he was the victim of physical abuse at the hand of an ex-boyfriend, something he says even his mom didn't know about.

Now, he admits to being in a much healthier relationship with someoneone else and is overall doing better physically and mentally. He hopes sharing his story will encourage others to get the help they need, too.

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