Same thing happened to me afy, after about a month on the diet i would be starving for breakfast and it was the biggest meal of my day, totally not what i used to do, i used to only have a coffee in the morning and then not eat till about 12. Also it has been mentioned that we dont change back to our girly way of eating just because we get a bfp, because that may be dangerous if we have conceived a boy as they need more nutrients in the first few weeks to stick, so keep it regular and healthy.