DazzleYou: Sorry to disagree with out, but headaches are not mostly caused by dehydration. That is certainly a consideration, but most headaches are caused by a combination of factors including stress, poor diet, vast changes in sleep cycles, head, neck, or back traumas and numerous other causes.
Caffeine can cause certain headaches, withdrawal from said stimulant can also. But caffeine can also be used to treat certain headaches as well.
People who have certain food allergies can certainly be affected by cheese, just as certain people my be affected in the same way by licorice.
Headaches are as varying as breeds of dogs. That is why my first question to her was to describe the pain she was feeling.
We need more docs like you in this area! (one that actually knows what he's talking about)