Carbo-fucking-hydrates ! Eating too many carbohydrates at night especially, which are converted to sugars in the body, causes a blood sugar spike and then subsequent drop over the course of the night, resulting in waking up with a migraine.

Big serves of chips, for instance, on top of sugary desserts will cause this.

I found this out on the net, not from my doctor. It caused a huge change in frequency and severity when addressed.

Eating like that, as you grow older, will gradually make you a diabetic.

Edit:- The other key was electrolytes. Drink electrolytes at the very first twinge of pain.