I’m a couple of days into the diet so far (7.5lbs lost in two days!), and am drinking lots of water, maybe 3-4 pints a day, but have also stopped caffeine because I only drink tea with milk, and I don’t really have the spare calories for milk currently. I’m not quite sure whether the headaches are just from the fluid loss or the caffeine withdrawal, but did anyone else have this? How long did it last?

My headaches were worse in the first week. I am now nearing the end of week two and not having headaches . You probably need to drink more water as dehydration will cause this. Good luck.

It does appear to have totally abated. They lasted about 2/3 days. Now one week in (and 17lbs down) and not getting any headaches at all 🙂