Beyonce performs at the 2014 Grammy Awards Tumblr

Beyoncé rocked the stage alongside husband Jay Z at the Grammy Awards Sunday night, wearing a Le Perla cage bodysuit that revealed her toned abs and derriere. The hot couple opened the awards show with a steamy rendition of their hit song “Drunk in Love.” While Beyoncé looked as sexy as ever, it didn't take fans long to comment on her physique, which looks a lot slimmer than it was during her “Bootylicious” days.

“Soooo nobody is gonna point out how skinny Beyoncé is now? [sic]” @Kocachanel wrote on Twitter.

@_KaelineAdkins_ wrote, “I don’t think I like Beyoncé that skinny, but I guess that’s what she wants.”

So how did Beyoncé lose so much weight?

Did Dancing Cause Her Weight Loss?

Queen Bey never just stands and sings. She's known as much for her amazing voice as for her dance skills. (“Single Ladies,” anyone?) She is the ultimate performer and entertainer, and always shows off dance moves throughout her concerts, especially during her many fast-paced songs. Dancing for the average-sized woman can burn up to 200-300 calories in only 30 minutes, and Beyoncé’s concerts are typically well over an hour long.

Beyoncé’s Exercise Regimen

Beyoncé undoubtedly trains hard to get through her nightly performances without being tired and out of breath. Last February, Beyoncé's personal trainer, Marco Borges, spoke to Life & Style magazine about how he helped whip the new mom into shape. She combines cardio, lunges and a diet full of veggies and lean meat to achieve her body. Borges said he put her on a partially vegan diet, with “one vegan meal a day, because this typically gets people to eat more greens than they normally would." He added, "Consistency is the key to success. I love running sprint intervals for quick cardio sessions and also ... running stairs."

Vegan Diet

Bey and rapper/producer husband Jay Z went on a vegan diet for 22 days last month. The plant-based diet may have a number of positive effects, including weight loss, improved heart health, and diabetes prevention or control. Unlike vegetarians, who eliminate meat, fish and poultry, vegans don't consume any animal products at all, including dairy and eggs.