Premenstrual symptoms (PMS) are characterized by a set of behavioral, somatic, and affective symptoms of varying severity that occur during the 7–10 days before the onset of menstruation and subside after the beginning of the menstrual flow. Although the etiology of PMS is largely unknown, current evidence suggests that they may arise from a decrease in brain serotonin neurotransmission. Starch dietary regimen may increase brain serotonin.

In this quasi-experimental study, we investigated associations between Starch dietary regimen and PMS in 14–19 years old high school students from October to January 2007 in Sari, the city in the North of Iran. 478 girls were selected for this trial. Participants were advised to consume a dietary regimen full of starch every 3 hours a day unless they were asleep. Symptoms were prospectively documented over 3 menstrual cycles with a daily rating scale that had 20 symptoms of PMS After 3 months data analysis was done.

PMS score was 12.85 ± 8.01 prior to dietary regimen, and at the end of first, second and third month following dietary regimen were 11.03 ± 7.59, 12.47 ± 7.79 and 11.13 ± 6.71 respectively (p = 0000). Mood score was 15.8 ± 10.02 prior to dietary regimen, and at the end of first, second and third following dietary regimen were 12.61 ± 9.34, 13.06 ± 8.13 and 11.46 ± 7.09 respectively (p = 0000).

Results of this study revealed that carbohydrate-rich diet can improve PMS symptoms. Therefore, we recommended codified teaching programs via health care staffs to students about the beneficial effects of diet on relieving PMS.