Typically the first few days you can really feel lousy. This is just your body going into ketosis. Usually by day 4 or so you feel much better. I also sometimes experience a slight metallic taste in my mouth but I checked with my Dr and he said it is just a side effect of being in ketosis.
Thank you for your inpute, I have been on the program for about 28 days and I have been feeling very nervous and anxious, I was doing great up until now, and when I spoke with my Dr. she never mentioned that I would have these side effects.
One thing they suggest for nervousness of lightheadedness is to try a cup of bouillon as your sodium might be low and it is a legal snack so it is worth a shot. let us know how you are feeling
Something that can cause nervousness and anxiousness is caffine. Our bodies are MUCH more sensitive to it when we're consuming much fewer calories. If you're taking in more that two caffinated beverages in a day, I'd reccommend cutting back to no more than two.