Vitamin B6 Supplementation Reduces Depression in College Women Taking Oral Contraceptives: A Randomized, Double-Blind Cross-Over Trial

Abstract

Abstract Objectives Oral contraception (OC) use has been linked to an increased risk of depression in college women and to poor micronutrient status. Of note, when compared to non-OC users, OC users have a heightened risk of low plasma concentrations of vitamin B6, a cofactor in the tryptophan-serotonin pathway critical to mood regulation. The purpose of this crossover study was to determine whether vitamin B6 supplementation impacted mood states and depression in college women using OC. Methods Participants were healthy and between 18–25 y, did not smoke or use dietary supplements, and used OC (estrogen with progestin) consistently for at least one year prior to the start of the study. The 12-week, randomized, double-blind crossover trial (4-week treatment periods [B6: 100 mg/d or control: placebo pill/d] separated by a 4-week washout [no pills taken]) was approved by the university Institutional Review Board, and participants provided written consent. Anthropometric measures, blood sampling, and diet and mood assessments were completed at the start of the trial and at weeks 4, 8, and 12. Participants (n = 8) maintained normal exercise and eating patterns the duration of the study and recorded pill consumption daily. The Profile of Mood States (POMS) and Beck Depression Inventory were used to assess affect. Plasma pyridoxal 5′ phosphate (PLP) concentrations were quantified by enzymatic assay. Repeated measures ANOVA was used to assess treatment effects. Results Plasma PLP concentrations averaged 66 ± 32 nmol/L at the start of the trial; one participant presented with marginal vitamin B6 status (20–30 nmol/L). Average vitamin B6 intakes did not vary during the trial (1.2–1.4 mg/d); whereas, vitamin B6 status rose significantly following the B6 supplementation period compared to the other three timepoints. POMS scores were not impacted by treatment; however, Beck Depression Inventory scores were reduced 30% by B6 supplementation in comparison to the control treatment (P = 0.047). Conclusions These preliminary data support a growing literature suggesting the benefits of B6 supplementation for reducing depression in young women using OC. Funding Sources This study was supported in part by the Graduate and Professional Students Association and the Office of the Vice Provost for Research.