I had headaches in the beginning too. Headaches are an unpleasant symptom of de-toxing. I don't drink caffeine, so it wasn't from that. Likely for me it was sugar.
The red food coloring used in a lot of stuff is a known headache/migraine trigger for many people and I know the Wildberry HNS has it, and I think the grape - so you may want to check into that.
I experienced the coldness symptoms of ketosis later on, but the headaches were only the first week or two.
Joined MRC August 6, 2012.