Table 4: Summary of the literature on relation between vitamin D and headache.

The first author (year)Study designPatient sample sizeType of headacheHeadache severity assessment Methods of vitamin D level assessment Mean of vitamin D level in patient (ng/mL)Effect/association of vitamin D (found by authors)

Kjaergaard et al. [28] (2012)Cross-sectional4061Migraine ( ) Nonmigraine headache ( )YesElectrochemiluminescent immunometric
assay
24.62
(migraine patient)
24.48 (nonmigraine headache)
Not associated
Knutsen et al. [33] (2010)Cross-sectional63Patients with chief complaint of headacheYesHigh-pressure liquid chromatography
mass spectrometry
(HPLC-MS)
14Associated
O’Brien et al. [29] (2010) Cross-sectional300Episodic migraine ( ) Chronic migraine ( )NoNot reported24.19
(episodic migraine)
23.19 (chronic migraine)
Associated
Krusz et al. [30] (2010) Cross-sectional100Migraine/ headache ( ) pain syndromes ( )NoNot reported29.3
(migraine/
headache)
28.2 (pain syndromes)
Not associated
Wheeler [14] (2008) Cross-sectional54Chronic migraineNoNot reported34.6Associated
Prakash [17] (2009)Case report8Chronic tension-type headacheNoNot reported7Effective
Thys-Jacobs [15] (November 1994)Case report2MigraineYesNot reportedNot reportedEffective
Thys-Jacobs [16] (October 1994)Case report2Menstrually-related migrainesYesNot reportedNot reportedEffective