I am also suffering from headache where I never had headache before (Whole 30). I am on day 15. Dull headache always there (started day 3) and it spikes to pretty miserable.
I thought it was the sugar (lack of) at first based on the description of "the hangover" in Whole 30 Guide. Now thinking... it's something MISSING from my diet. Could that be??
Other than that - I'm loving the food, not feeling deprived, no need for snacking (unless I plan it pre- post- workout).
I looked at what lhowe wrote for food - I'm similar with food (breakfast usually sweet potato egg and saute kale, zoodles or roast veggies, lots of recipes from Whole 30 Cookbook and Guide (yum!), all home made with compliant ingredients).
I'm tired of the headache - feels like a perpetual hangover! Miserable!!