In all the ''atkins'' books the warnings are clear,''consult your physician first'' if you have one you can trust. Seriously though, if you have a pre existing condition, like many people who are seeking out alternative health care have, you can hardly blame Atkins for that. Appendicitis and other digestive disorders don't just appear in two weeks.although i imagine any extreme change to your system could exacerbate your pre existing condition. Or maybe your not a ''protein type''. I don't believe Atkins meant for everybody to eat this way,but he had to destroy the myths that protein and fat are bad for everyone. In one of Atkins earlier books there was a chapter called the ''millet diet'' that refered to people who were more suited to carbs. After reading ''the Metabolic typing diet'' by Wolcott and Fahey and taking thier test to help to determine if you are a ''protein,mixed,or carb type'' I find that i am a protein type and the Atkins diet was right on for me. Also 30 yrs ago i had hepatitis and yellow jaundice and have ever since been concerned about my liver. I've been on the atkins diet for 15 yrs and my liver seems all the better for it.And no signs of hepatitis on my last few tests. And to those of you who are concerned about losing to much weight to fast, maybe you should try something else.