These days, Beyonce Knowles seems to be Hollywood’s most unstoppable tour-de-force.

A veteran of the music business at just 27, the star graces the cover of the April issue of Vogue magazine to discuss singing for the president, her status as a role model and of course, those gorgeous curves of hers.

Indeed, Knowles has been known to easily transform her body shape for various roles, famously losing twenty pounds for her role in Dreamgirls, then gaining an additional 20 for Cadillac Records.

PHOTOS: Click here for photos of Beyonce in Vogue and more.

“It’s easy for me to gain weight,” she says. “I’m not a naturally stick-thin girl. I’m not heavy but Im not skinny either.”

Coupled with her amazing talent, it’s easy to see why the star’s self-confidence and poise have made her a role model to young girls everywhere, including Sasha and Malia Obama.

“The amount of influence I have on these young girls is scary sometimes. But I also understand how lucky I am to have that.”

Pick up the April issue of Vogue on newsstands March 24.

LINK: Click here for additional photos of Beyonce and the full feature at Vogue.com

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