Fasting and migraine: a systematic review of frequency, severity, and clinical implications

Background Migraine is a prevalent neurological disorder that impairs daily functioning and productivity. Fasting has been frequently reported as a migraine trigger, potentially due to mechanisms such as hypoglycemia, dehydration, and caffeine withdrawal. Religious fasting during Ramadan presents a unique model to explore these effects. This systematic review examines the impact of fasting—religious and non-religious—on migraine frequency and severity. Methods We conducted a systematic review following PRISMA guidelines to assess the impact of fasting on migraine frequency, severity, and quality of life. Eligible studies involved adults with migraine undergoing various fasting regimens, including Ramadan fasting, compared to non-fasting conditions. We searched PubMed, Cochrane Library, and ScienceDirect in April 2025 using terms like “Migraine,” “Fasting,” and “Ramadan Fasting.” Studies were included if published in English with full-text availability and relevant outcome data. Risk of bias was assessed using the Newcastle-Ottawa Scale, and due to heterogeneity, findings were synthesized narratively. Results Seven studies met the inclusion criteria, four of which focused on Ramadan fasting. Five out of seven included studies reported an increase in migraine frequency and/or severity during fasting, while two studies reported no significant change. Identified contributing factors included dehydration, sleep disruption, and caffeine withdrawal. Two studies highlighted fasting as a common migraine trigger, while one ranked it as the second most-reported trigger after stress. Conclusion Fasting—particularly during Ramadan—is associated with an increased migraine burden, likely mediated by modifiable factors such as dehydration, disrupted sleep, and caffeine withdrawal. These findings highlight the need for anticipatory guidance and preventive strategies to help migraine patients safely observe fasting. However, the overall evidence remains limited and heterogeneous, primarily derived from observational studies.