January 17, 2014 - 14:23 CET hellomagazine.com Michelle Obama will celebrate her 50th birthday with a special dance party at the White House, arranged for her by President Barack Obama. Superstar singer Beyonce will reportedly perform Michelle Obama will celebrate her landmark 50th birthday on Friday with a big dance party at the White House. The soiree has been organised for the first lady by her husband President Obama, and details of the event remain a closely guarded secret to maintain an element of surprise for Michelle. Guests have been told to be prepared to dance though, and to eat before they come. "There's one thing I can tell you for sure… people will move, said Valerie Jarrett, a senior White House adviser. While it hasn't been confirmed, it is thought that Beyonce has been asked to sing at the party. The superstar singer, a close friend of the Obama family, famously serenaded Barack and Michelle at an inauguration ball in 2009, and performed the national anthem at the president's second swearing-in ceremony at the Capitol last year. Meanwhile, the famously fit first lady recently spoke about maintaining her health in the future. In an interview ahead of her big birthday, Michelle told People magazine, "I don't obsess about what I eat, but I do make sure that I'm eating vegetables and fruit. And as everyone knows, I do exercise. She also said that she wouldn't rule out the use of plastic surgery - "Right now, I don't imagine that I would go that route, but I've also learned to never say never" - and revealed that her workouts have evolved from weight-bearing and cardio exercises to include things like yoga. Asked whether she had peaked at 50, Michelle said that being first lady is "pretty high up". She went on to say that she feels her life is "ever-evolving" and that she doesn't have the right to "just sit on my talents or blessings". "I've got to keep figuring out ways to have an impact, whether as a mother or as a professional or as a mentor to other kids," Michelle said, noting that daughter Malia, 15, will be in college when the family leave the White House in January 2017. Youngest daughter Sasha, 12, won't be far behind. "At that point in life, whoa, the sky is the limit," she said.