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"I feel beautiful right after I've worked out," says the 32-year-old star of Lucky You. "I feel like I've changed the shape of my body into something more flexible and strong."
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"I admire people with beautiful skin, so I really like getting compliments on my skin," says the singer, 23. "I'm always examining it with a large mirror and always looking at the flaws."
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"The best thing about going without makeup is that it takes a lot less time to get ready," says the 19-year-old singer. "You don't have to worry about mascara spilling or eyeliner running or about touching up during the day. You can wash your face at any time. You feel comfortable and free."
Listen to Rihanna talk about when she feels the most beautiful
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"There's a vulnerability to being photographed without having your eyes defined or your eyebrows filled in, but I don't wear a lot of makeup in my personal life," says the actress, 25. "I find that men, in my past, have preferred me without it. They always said, 'No, take that off.' "
Listen to Jessica talk about when she feels the most beautiful
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"I tend to leave the house without makeup all the time. I'm kind of lazy that way," says the The Office star, 31. "Smiling is definitely one of the best beauty remedies. If you have a good sense of humor and a good approach to life, that's beautiful."
Listen to Rashida talk about when she feels the most beautiful
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"I always thought my jawline was manly. I have this pockmark on my chin from when I was 9," confesses the actress, 27. "I used to get freaked out about it because people thought it was a pimple. But those are the things I've become really comfortable with as I've gotten older. My scars."
Listen to Rosario talk about when she feels the most beautiful
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"My mom is white, so I grew up thinking that women should be fair and blonde," says the actress, 26. "Things I was made fun of for – thick lips and a curvy body – got better as I got older."
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"I don't feel the need to impress anymore. I've worked for a long time to get where I am, and now I can be comfortable in my own skin," says Simpson, 26. "I feel more in control of my life. Outward appearance is just secondary to the confidence that I feel inside."
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"I see myself as a short little person who looks very young," says the actress, 25. "I don't pay much attention to physical stuff; it's about the whole picture and just being comfortable with who you are."
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"I get my hair and makeup done at work. After a while you get tired of being touched. When you do it all the time, it's refreshing when you don't do it," admits the Desperate Housewives star, 32. "Tony [Parker, her fiancé] says he loves the way I look when I wake up in the morning, which is the reason why I'm marrying him."
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