Thought I would post since I found a lot of questions to the question regarding headaches. I am on Day 4 and have had the same headache problem. My head aches start in the early afternoon also (like many other posters). They start with Migraine like symptoms (tunnel vision) and then result in Pain. Without going into everything I have eaten, I have found relief in Salt!
I eat a bag of Salted Cashews or Almonds when the tunnel vision hits and I generally have a mild headache, but within 30-45 minutes the headache is gone. I hope this helps for you all.