Im on day 12 rebar and plan on going to atleast 20 and beyond depending. First two days went fine, little hunger for me, days 3,4,5 I had considerable chest pain, palpitations and racing heart primarly at night. It got pretty bad and I almost broke the fast but knew that these things are very complicated and I felt I wasn't having heart trouble per se which the conclusion most might make, but my body was struggling to adjust. I found that drinking lots of water about a quarts slowly over the course of 30 + minutes brought the palpitations and racing heart somewhat under control but it was a difficult few days. Then, it all started to settle down, and by day seven chest pain was 90% reduced as were the palpitations, racing pulse completely gone. Its been smooth sailing from there though no changes in my CFS symptoms. I have zero hunger, modest dizziness upon standing, no worse than my usual orthostatic symptoms, a little weak from the fast, but all in all its going very well. Had my electrolytes checked day seven and sodium and chloride were low and I think its because I was drinking too much water (gallon and half per day). Cut way back and getting electrolytes checked again this week. One thing I can feel the fast working on is my gut. Have a lot of gut pain and numbness down there, I think its a vagus nerve, nerve damage issue and the fast is working on it somehow. Heavily coated tongue on the fast which is typical.