Whether he's in his office or at home, Cowell never misses his weekly shot. Before the needle goes in, Cowell -- who was terrified of needles as a child -- has his arm frozen with a spray so it won't hurt.
"Even when I'm having a viewing session with producers," Cowell says, "she just sticks a needle in me and we carry on doing whatever we're doing."
Cowell remains connected to the IV for around half an hour. "When you have it done, it's an incredibly warm feeling," he explains. "You feel all the vitamins going through you. It's indescribable but very calming, and then it gives you energy for a good few days afterwards."
The procedure was recommended to him by former UK X Factor judge Dannii Minogue, 39. Since his first shot, Cowell has been a huge advocate for the weekly vitamin boost.
"Everyone I've recommended it to, they've absolutely loved it," he tells GQ. "It sounds odd, but when you have it, it is fantastic. One girl came down and actually had two orgasms during the treatment."