Should You Be Injecting Vitamin B-12 Into Your Ass?

B-LIST Madge, Justin Shots at Vitamin B-12 are totally the new coke! Last night, while introducing Madonna into the Rock 'n' Roll Hall of Fame, Justin Timberlake said that Madge once plunged a syringe of B-12 into his ass to help him beat a case of fatigue. Lying pitcher and one-time Hall of Fame candidate Roger Clemens claims he too was getting regular ass injections of the vitamin. Anna Nicole Smith even had the stuff in her system at the time of her death! So what does B-12 actually do, other than make you the type of person who walks around with a bag full of needles (Madonna) or the type of person who needs a legal cover to hide the fact that you're using steroids (Roger)?