Friday The 13th: Superstitious Celebrities Reveal Their Quirky Rituals By Justine Ashley Costanza @Justine__Ashley On 07/13/12 AT 12:27 PM In a 2012 interview with Vanity Fair, the pop sensation shared her fear that casual sex could threaten her artist development. “I have weird superstitions about sex,” Gaga has said. “If you’re not having sex with someone who really cares about you or who really loves you they can screw up your energy. I have this weird thing that if I sleep with someone they’re going to take my creativity from me through my vagina.” Photo: Reuters Before the birth of her son, Aleph, Portman was "very superstitious" when preparing for his arrival. The "Black Swan actress revealed that she wouldn't be putting together the baby's room prior to his birth. "I’m very Jewish that way. We don’t do that," Portman said in 2011. Photo: Reuters Superstition has proved pricey for the AC Milan player. According to Men's Health, the soccer star/underwear model is known for wearing a brand new pair of cleats before each game. Photo: Reuters "What to Expect When You're Expecting" star Cameron Diaz has admitted to believing in some superstitions but bravely facing others. “I knock on wood all day long...constantly," the actress told Cosmopolitan. "But I’ve also flown on Friday the 13th in a storm with a black cat on my lap, so I’m not that superstitious." Photo: Reuters The hunky "Total Recall" star has talked about wearing the same boxers whenever production starts on a new film. "I don't wear them to the discos and the clubs," the actor revealed in 2004. "They're only for the first day of filming. Shamrock shorts - not very glamorous!" Photo: REUTERS/Mike Cassese The singer's beau, Eric Johnson, reportedly proposed on 11/11/10 at exactly 11pm. “A numerologist told Jessica that the number 11 was going to be an important number in her future, and Eric knew it. So he waited until November 11 to pop the question," purported the Enquirer. Photo: Reuters Alba became quite superstitious while pregnant with daughter Honor in 2008. During her baby shower, the actress gave guests prayer bracelets and asked that they not be taken off until the baby was born. "Jessica made sure everyone was wearing a leather bracelet before they all launched into a 'life, love, health' prayer. She then told them they aren't allowed to take off the bracelets until the baby is born," an onlooker told Hip-Hop Elements. Photo: Reuters The Broadway legend and "Glee" guest star has shared her trepidations when it comes to walking under ladders. "I have a fear of walking under ladders. It's probably because it'd be much easier for me to do so than many people. I also say a prayer right before I got out on stage so that lights never fall on me." Photo: Reuters In a 2009 interview with the Tonight Show, Swift revealed that her lucky number is 13! “I was born on the 13th, I turned 13 on Friday the 13th, my first album went gold in 13 weeks…also my first song that ever went #1, it had a 13 second intro.” Photo: REUTERS/Richard Brian Back in May, the New York Post claimed that one of the biggest names in television plans his day around his superstitions. "The Today Show" host is said to arrive at work at the exact same time each day and takes the same route to his dressing room. Photo: Reuters In a 2010 interview with "The Tonight Show," the "Wanderlust" star talked about her strict flying rituals. “If I walk onto an airplane, I always have to go on with my right foot first and tap the outside of the plane,” Aniston said. “I have always done it. For luck. Someone told me to do it and I don’t remember when that was. But it’s kind of stuck.” Photo: Reuters The "Dark Knight Rises" star is superstitious about superstitions! The intense actor constantly defies common beliefs surrounding bad luck. "I walk under ladders, I do all that stuff. I do it on purpose. I like provoking superstitions," he has said. Photo: Reuters Previous Next In honor of Friday the 13th, here are thirteen stars who believe in superstitions.