Cameron Diaz was a "miserable" teenager because of her bad acne.
The 41-year-old actress admits she could eat whatever she wanted when she was younger but her love of junk food took a toll on her skin and made her dread leaving her house.
She told the February issue of Seventeen magazine: "You might think my life is always totally glam, but I used to have horrible acne - deep, boiling pimples - the kind that hurts so badly, I didn't want to leave my house. My friends said they didn't notice, but I'd say, 'It's the only thing anyone can see!' No amount of concealer and foundation could take away the texture of my skin, the embarrassment I felt, or the pain of those raging pimples. I was miserable."
She added: "At the same time, I was this skinny girl who could eat anything I wanted without gaining an ounce - so I did. I was the poster child for being both skinny and unhealthy - and I had the zits to prove it. I thought I'd tried everything to make my skin clear up, but I didn't realise all that fried, greasy, processed artificial crap was setting off a hormonal surge that sent my skin into crazy town!"
The 'Counsellor' star claims her skin immediately started clearing up when she began eating healthier and working out regularly.
She said: "Once I cut out the junk, I saw such a major difference that I felt like an idiot. It not only cleared up my acne, but it also gave me this huge amount of energy. I went from focusing on how my face looked to focusing on all the awesome things my body is capable of."