You’re eating too much. I know I know I’m stating the blindingly obvious right off the bat, but obvious for a reason. Occum’s razor states that when presented with multiple theories the simplest is the best and most likely. Your body requires food to operate. In order to function properly you need to eat. But, there is a limit as to how much food your body requires. Put simply; if you lead a sedentary lifestyle with the only activity being moving from your desk to the sofa your calorie requirements will be significantly less than someone who cycles to work and goes to the gym 3 times a week. If you are eating too much, you won’t lose weight. The National Health Service recommends daily calorie intake to be 2000 calories for women, and 2500 for men to maintain their weight.