Recurring/frequent headaches can often be the result of a "hidden" food/chemical allergy or intolerance.
I used to get headaches at least once a week, ( aswell as frequent colds, painful bloated tummy, and later on mood-disorder and depression ), until I cut out gluten.
I discovered that whereas cheese, chocolate, oranges, tea and coffee had seemed to be the triggers for headaches and gut problems, if/when I excluded gluten this stopped happening. The thing with hidden food intolerances is that are often so used to the general effects that you don't notice/know about them, and think that things like headaches etc must be related to one-offs or relatively infrequent factors.
It is definitely worth investigating diet if you are plagued by headaches, because, as still larva says, they are a signal, telling you that something is wrong.
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