What kind of foods were you getting your sugar from? What were you drinking with your white-flour-based foods?
If you were getting sugar from soda, coffee drinks, etc, or if you were in the habit of grabbing a muffin and a cup of coffee and now you're skipping the coffee as well as the muffin, then you might be having caffeine withdrawal. You also might be drinking less liquid, so you're getting dehydration headaches.
Blood sugar fluctuations might be the culprit, but also look at what *else* you've changed. You've probably made some non-food changes, like a slight change in bedtime or wakeup time, etc. Any of those little things can trigger a headache, too.
| current weight: 132.0