Objective: Premenstrual syndrome (PMS) affects 20%-30% of women but current medical treatments are limited in their efficacy. The objective of this study was to compare efficacy of a broad-spectrum micronutrient formula (consisting mainly of minerals and vitamins) to a single vitamin (B6) for treatment of PMS, for which B6 has already been shown to be efficacious. Methods: This double-blind, randomized, treatment-controlled trial allocated 78 (72 completed) regularly menstruating women with PMS to consume micronutrients or vitamin B6 (80 mg/day) daily following a two-cycle baseline period, for three menstrual cycles. The primary outcome measure, Daily Record of Severity of Problems (DRSP), established PMS as well as tracked change in five PMS symptoms: psychological, somatic, total symptoms, impact ratings, and worst day ratings. Results: Linear-mixed model analyses indicated both treatments produced comparable reduction in PMS symptoms with medium effect sizes (ES) across all PMS variables as measured by the DRSP (micronutrient ES = 0.50-0.56; B6 ES = 0.43-0.56), with 72% of the micronutrient and 60% of the vitamin B6 group identified as in full remission in PMS symptoms after three cycles. The micronutrient-treated participants showed greater improvement than the B6 group (between group d = 0.51, p < 0.05) in health-related quality of life. For those women (n = 28) who met criteria for premenstrual dysphoric disorder (PMDD), the DRSP ES were larger for those who had been in the micronutrient condition (ES = 1.28-1.67) as compared with those on B6 (ES = 0.50-0.75), although the group differences were not statistically reliable. There were no group differences in side effects, nor any serious adverse effects reported. Conclusions: Both treatments provided similar benefit for reducing PMS symptoms, with greater effect of micronutrients on quality of life as well as potential clinical benefit of micronutrients for PMDD. This study provides further efficacy data on B6 and also identifies the nutritionally broader spectrum intervention as possibly having specific advantages for those whose symptoms are more severe. As this is the first study to investigate these treatments for PMDD, systematic replication is required.
Keywords: micronutrients; premenstrual dysphoric disorder; premenstrual syndrome; vitamin B6.