Christina Aguilera hit the red carpet at the 2013 American Music Awards on Sunday, Nov. 24 showing off her dramatic weight loss in a sexy white cutout dress. The "Beautiful" singer wore a white Maria Lucia Hohan gown paired with Christian Louboutin shoes, a Jimmy Choo bag and Lorraine Schwartz jewelry, Hollywood Life reports.

Aguilera looked noticeably tinier than last year when she walked the red carpet in a long flowing purple gown. "The Voice" coach has been impressing fans and critics with her new svelte shape. During the awards show she took the stage in a simple black dress as she belted out her latest single "Say Something" with A Great Big World.

In September, Life & Style magazine revealed how the pop star shed the reported 50 pounds. A source said Aguilera cutback on her alcohol intake and cut out unhealthy foods. Reportedly the 32-year-old started her day by eating blueberries, turkey bacon and half an avocado. For mid-day snacks she chose shrimp cocktail or celery sticks with almond butter and for lunch the source said she ate chicken breast over a healthy salad and skipped the creamy dressing.

"[Christina] is as happy as can be, as fit as can be and as full of life as can be," Mark Burnett, producer of "The Voice" said. "She looks amazing."

For dinner Aguilera would enjoy a glass of wine with fish curry or chicken. She first showed off her significant weight loss during the season finale of "The Voice" after taking a short break to focus on her music career. Apparently while away from the spotlight Aguilera used the time to get back in shape enlisting the help of celebrity trainer Tee Sorge. Sorge helped the singer get in shape for her role in "Burlesque" back in 2010.

"A lot of people were on her about her weight and it depressed her," a source told US Weekly. "She went through a bad time because of the criticism."

The source said she signed up for the Fresh Diet Program, a 1,600 calorie-a-day plan that allowed her to choose from a variety of healthy meal options.

"She did it all on her own. She goes online and picks out her food," the source said. "It's more of a mind-body thing for her. She believes in exercise that she enjoys, doing strength work as opposed to intense cardio."