Aims: To evaluate the efficacy of sucrose in the prevention of migraine attacks. Methods: Two randomized double-blinded pilot trials were conducted, one in college students and one in adults. Migraineurs were randomized into two groups that each received an oral liquid: for students, sucrose 5 g/day (s-group; n = 12) or glucose 2.5 g/day (g-group; n = 10) for 3 months; and for adults, sucrose 5 g/day (s-group; n = 10) or fructose 2.5 g/day (f-group; n = 9) for 6 months. The primary endpoint was the frequency of migraine attacks per month, and the secondary endpoints were mean duration and severity of migraine per attack. Continuous measurements were described as mean ± standard deviation (SD). The overall significance of the effects between different groups was tested using repeated measures analysis of variance (RANOVA), and the efficacy was evaluated using an intent-to-treat analysis. Results: Migraine frequency in the students declined significantly in the g-group (mean reduction ± SD: 0.65 ± 0.71; P .01), but not in the s-group (0.33 ± 2.02; P = .58). RANOVA results suggested that the secondary endpoints significantly declined over time (all P .01) with no differences between the groups. In the adult trial, mixed-effects model analysis showed that both the primary and secondary endpoints significantly declined over time with no significant differences between the groups. Conclusion: Long-term consumption of a 5-g dose of sucrose for adult migraineurs or a 2.5-g dose of glucose for college student migraineurs may be as effective as preventive treatments. Keywords: migraine, prevention, sucrose