At baseline and during the observation period patients will be seen at the Headache Outpatient Clinic of our department at one month intervals. At each visit they will be given a form to be filled at home, summarizing the number of the monthly headache attacks, the severity of each one graded from 0.1 to 3 from mild to severe pain, and how many times they assumed pills for the therapy of the attacks during the last month. Headache attacks with severe pain will be considered those receiving a score > 2.5. Moreover, at each visit patients will fill-up a food questionnaire, validated in comparison to the 7-day food record (12), with the help of a well trained dietician. Data are expressed as daily percent caloric intake from each macronutrient and as the weekly number of a medium size serving.