I have an issue.
Every time I start to eat healthy (cut out the junk food, replace with veg and reduce carbs slightly although not to a LCHF way) i have been sticking to 1200 cals a day (just under) but I can't poo! 
It happens every time and it's uncomfortable and it stalls the scales going down.
I don't even get the urge to go anymore like there's just nothing there! 
I am drinking a lot of water and I eat a lot of veg some fruit, lean meats and a small amount of grain, hardly any dairy. I don't understand it but I'm at the point of relying on laxatives which I don't think is healthy.