Gum-chewing and headache: an underestimated trigger of headache pain in migraineurs?

Tension-type headache and migraine are currently considered the second and third most frequent human diseases. Since a variety of conditions that involve the temporomandibular joint and chewing muscles are frequent causes of orofacial pain, the aim of this article was to review current published evidence about the potential relationship between gum-chewing and headache. A systematic electronic search performed on Medline, Scopus and Web of Science using the keywords "headache" or "migraine" and "chewing" allowed to finally identify 1 cross-sectional, 1 observational and 3 randomized studies, along with 3 case reports about the potential association between gum-chewing and headache. Despite the limited evidence, it seems reasonable to suggest that headache attacks may be triggered by gum-chewing in migraineurs and in patients with tension-type headache. Opposite results were obtained in non-migraineurs, since in none of these studies an increased prevalence of headache pain was reported after gum-chewing. Although larger randomized studies will be necessary to definitely establish the relationship between gum-chewing and headache across different populations, it seems cautionary to suggest that subjects with migraine or tension-type headache should avoid or limit gum-chewing in their lifestyle.