Lately celebrities have been opening up about their unconventional bathing habits and Jake Gyllenhaal has joined the likes of Mila Kunis and Ashton Kutcher in their anti-bathing sentiments. In a recent interview with Vanity Fair , the actor revealed that 'more and more I find bathing to be less necessary, at times. I do believe, because Elvis Costello is wonderful, that good manners and bad breath get you nowhere. So I do that. But I do also think that there's a whole world of not bathing that …