“52? Oh my God, bye everyone, I’m leaving,” he commented in shock, pretending to walk off the set.
Naga was left in stitches by his reaction to her joke.
Charlie on the other hand added: “So I am going to take this challenge seriously,” to which Naga chimed: “What makes you think I didn’t?”
After Charlie’s low guess of 31, Owain thanked the “great lighting in this studio” and revealed he actually just turned 37.
BBC Breakfast airs every day at 6am on BBC One.