Beyoncé's sexy performance during the 2014 Grammy Music Awards revealed a slim down version of the "Drunk in Love" singer, and she can credit her weight loss to a vegetarian lifestyle.

According to E! News, the singer's white lace Grammy dress was designed by Project Runway winner Michael Costello. Costello revealed he was concerned the dress he sent over wasn't going to fit probably, but turns out needed to be a size smaller than he expected.

"It was incredible! We didn't have any of her sizes or measurements," Costello told E! News. "The dress was just made to fit a sample mannequin. It's smaller than a size 4. She is tiny! That dress is at least a 2/4. She looks amazing. I just love the way it all came together. Ty [Bey's stylist] knew it was going to fit."

"At first I was a little concerned with the pieces I gave. Maybe it needs to be smaller or bigger," Costello added. "When you send something to Beyoncé, you're just a little concerned, but Ty knew. Ty knew the fit."

According to the Mirror U.K., Beyoncé and her husband Jay Z both decided to engage on a vegan lifestyle for 22 days in January. Before their vegan diet, the couple decided to substitute red meat for fish and switch out simple carbs like pasta with quinoa.

Together the couple has reportedly lost 110 lbs., with Beyoncé losing 70 lbs. since giving birth to their daughter Blue Ivy Carter and Jay Z shedding 40 lbs. During her behind-the-scenes documentary series for her surprise album, Beyoncé explained why she was eager to show off her new body.

"I was 195lbs when I gave birth, and lost 65lbs. I worked crazily to get my body back. I wanted to show that you can have a child and you can work hard and you can get your body back," Beyoncé said.