My son has been back and forward to GP and hospital for nearly three years years but to no avail with this problem. He has been given Movicol to take daily but we have no idea why he retains weight and is so often constipated. Have tried cutting out various food types I.e. dairy but nothing helps. Would greatly appreciate anyone who can offer some help. Doctors seem to just say it's the way he is and we just have to deal with it. He is picked on at school for his size and as he gets older this is really affecting his confidence. Seems to have stated at around age 7. Many thanks.