My center says that you may experience headaches when you get into ketosis. I looked this up and some of the symptoms such as cold hands and feet are some of the things I was experiencing too. I don't know if that is you guys reason for having headaches but it could be?
It could also be the caffeine withdrawals, in the beginning I had headaches (nothing like a migraine though) from the withdrawals when switching to decaf coffee (still miss my leaded coffee). It only lasted about 4-5 days and since then I've had no other problems, just minor aches and pains from getting older *sigh*.
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.
I will have to look at everything. I know strawberries and red onions trigger migraines for me. Never even thought about the red dye. I didn't have a headache yesterday.. I also cut back on my vit b. wondering if that had anything to do with it.