You are given a passage. Using the information present in the passage, you need to classify it into one of the 10 topics: 0 - 'Society & Culture', 1 - 'Science & Mathematics', 2 - 'Health', 3 - 'Education & Reference', 4 - 'Computers & Internet', 5 - 'Sports', 6 - 'Business & Finance', 7 - 'Entertainment & Music', 8 - 'Family & Relationships', 9 - 'Politics & Government'.

There are several possible causes for headaches. According to a Chiropractor friend of mine, dehydration is a major cause. For example, too many Margaritas one night can leave you seriously dehydrated, hung over and with a headache the next day.
Other causes are stress, allergies, etc. Dr. Hoffman's reference below explains some of these in detail.
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