Changing tastes

I have always eaten and enjoyed huge amounts of vegetables and salad but right now even the thought of eating vegetables or the smell of them cooking makes me lose my appetite. It's so strange as I have always favored healthier foods but now it's the complete opposite and I would rather eat a burger and chips or chocolate and cake which I havent eaten for years. Had anyone else experienced this? I have no pregnancy nausea at all, its just more of a food aversion.