Slim fast does not work - well ok it works but after you go off it again you gain all the weight back. I thought the Atkins diet worked, but since you said that you gained 4lbs it must not be working for you. What i would suggest is go ask a doctor. He/she would be able to help you to loose weight and also find an answer to why you dont urinate much even though you drink 9 cups of water a day. Good luck to you!