Abstract
Background: Premenstrual syndrome (PMS) alludes to a cyclic advent of somatic and psychiatric symptoms that affect some women of reproductive age. Some studies demonstrated that vitamin D was associated with premenstrual symptoms. Objective: The aim of this study was to evaluate the effect of vitamin D supplementation in the treatment of PMS in vitamin D-deficient young girls. Methods: In this randomized double-blind placebo-controlled trial, 130 vitamin D-deficient girls aged 18–30 years, with PMS, were randomly divided into 2 groups and received a 2,000 IU vitamin D tablet (n = 64) or a placebo (n = 66) every other day for 12 weeks. At the beginning and at the end of week 12, serum 25(OH)-D, premenstrual symptoms, anthropometric indices, dietary intake, physical activity level, and sun exposure were evaluated. Statistical analysis was performed using SPSS version 20. p < 0.05 was considered statistically significant. Results: Serum 25(OH)-D levels were significantly elevated in the vitamin D group in comparison to the placebo group after 12 weeks (p < 0.001). There was no significant difference between the 2 groups with regard to 14 symptoms of PMS after 12 weeks of intervention, even after adjustment for the baseline values of anxiety, weeping, and hypersomnia (for all symptoms, p > 0.05). However, in the vitamin D group, scores of nervousness (p < 0.001), job activity reduction (p = 0.01), social activity reduction (p = 0.01), fatigue (p < 0.001), and physical symptoms (p = 0.00) were reduced at the end of the intervention, and these changes were statistically significant compared to baseline. However, these alterations did not reach significance compared with the placebo group (p > 0.05). Conclusion: It seems that 2,000 IU vitamin D consumption in the vitamin D-deficient young girls with PMS every other day for 12 weeks had no significant impact on other PMS symptoms.