Jay Z revealed yesterday that he and his wife Beyoncé are going vegan until Christmas Day. His "22 Days Challenge" will require the hip-hop power couple to remove meat and animal products from their diets.

"Psychologists have said it takes 21 days to make or break a habit. On the 22nd day, you've found the way," Jay Z wrote on his Life + Times blog. "On December 3rd, one day before my 44th birthday, I will embark on a 22 Days challenge to go completely vegan, or as I prefer to call it, plant-based!! This all began a few months back when a good friend and vegan challenged me to embrace a 'plant-based breakfast' every day. It was surprisingly easier on me than I thought..."

The "Holy Grail" rapper then explained why he waited until now to practice veganism and the special meaning behind the challenge. "There's something spiritual to me about it being my 44th birthday and the serendipity behind the number of days in this challenge; 22 (2+2=4) coupled with the fact that the challenge ends on Christmas Day," Hov wrote. "It just feels right!"

Hov added that the challenge is "a spiritual and physical cleanse." He pledged to post his progress and asked any "professional" vegans for restaurant tips. "I don't know what happens after Christmas. A semi-vegan, a full plant-based diet? Or just a spiritual and physical challenge? We'll see..."

He ended the post saying, "Best of luck and health!" and confirming that his wife is with him on the vegan challenge. "P.S. B is also joining me," Jay Z wrote.