NEW PIC: Christina Aguilera Debuts Slimmer Bod in Tight Black Dress

Christina Aguilera in Los Angeles, CA on April 12, 2012. Credit: FameFlynet

Christina Aguilera has turned over a new leaf, and underneath it has come more covered-up wardrobe choices.

On Thursday in Los Angeles, the Voice coach, 31, showed off her slimmed-down figure in a casual but form-fitting long-sleeved dress, black tights and leopard-print Christian Louboutin heels.

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It's no secret that the singer has done a 180 with her style recently. After filming The Voice auditions in a saucy black, cleavage-baring mini, Aguilera has switched up her wardrobe for the recent live performances, sporting more modest dresses and softer hair and makeup.

Christina Aguilera appearing on "The Voice"Credit: Colleen Hayes/NBC

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"I've been through my highs, I've been through my lows; I've been through the gamut of all things in this business," Aguilera shared about her look with Marie Claire magazine in February. "Being too thin. Being bigger...It's noise I block out automatically. I love my body. My boyfriend loooooves my body. My son is healthy and happy, so that's all that matters to me."