Underweight, obesity may increase risk for migraine

Underweight and obesity are associated with increased migraine risk, according to a review published in the July/August issue of Headache: The Journal of Head and Face Pain.

Fahimeh Martami, Ph.D., from the Tehran University of Medical Sciences in Iran, and colleagues conducted a systematic review and dose-response meta-analysis to examine the association between body mass index (BMI) and primary headache disorder subtype. Data were included from 41 observational studies with 154,044 cases and 792,500 participants.

The researchers found that compared with those with normal BMI, participants who were either underweight or had obesity had an increased risk for migraine (odds ratios, 1.21 and 1.28, respectively). Limited evidence was seen to support the association between BMI and risk for other subtypes of primary headache disorder. The association between BMI and migraine was nonlinear; the risk was lowest with BMI around 20 kg/m² and increased at BMI values above 29 kg/m².

"This meta-analysis suggests through a nonlinear association an increased risk of migraine among individuals who are either underweight or obese," the authors write. "These results support the recommendation that normal BMI is probably associated with a lower risk of migraine."