Vit D

Dietary B vitamin intake and incident premenstrual syndrome1–3
Patricia O Chocano-Bedoya, JoAnn E Manson, Susan E Hankinson, Walter C Willett, Susan R Johnson, Lisa Chasan-Taber, Alayne G Ronnenberg, Carol Bigelow, and Elizabeth R Bertone-Johnson
ABSTRACT Background: Thiamine, riboflavin, niacin, vitamin B-6, folate, and vitamin B-12 are required to synthesize neurotransmitters that arepotentially involved in the pathophysiology of premenstrual syndrome (PMS). Objective: The objective was to evaluate whether B vitamin intake from food sources and supplements is associated with the initial development of PMS. Design: We conducted a case-control study nested within the Nurses’ Health Study II cohort. Participants were free of PMS at baseline (1991). After 10 y of follow up, 1057 womenwere confirmed as cases and 1968 were confirmed as controls. Dietary information was collected in 1991, 1995, and 1999 by using food-frequency questionnaires. Results: Intakes of thiamine and riboflavin from food sources were each inversely associated with incident PMS. For example, women in the highest quintile of riboflavin intake 2–4 y before the diagnosis year had a 35% lower risk of developing PMSthan did those in the lowest quintile (relative risk: 0.65; 95% CI: 0.45, 0.92; P for trend = 0.02). No significant associations between incident PMS and dietary intakes of niacin, vitamin B-6, folate, and vitamin B-12 were observed. Intake of B vitamins from supplements was not associated with a lower risk of PMS. Conclusions: We observed a significantly lower risk of PMS in women with high intakesof thiamine and riboflavin from food sources only. Further research is needed to evaluate the effects of B vitamins in the development of premenstrual syndrome. Am J Clin Nutr 2011;93:1080–6. INTRODUCTION

mine, niacin, riboflavin, vitamin B-6, folate, and vitamin B-12 are involved in the metabolism of neurotransmitters through different mechanisms. Riboflavin is needed to activate vitamin B-6,which is a cofactor in the generation of serotonin from the amino acid tryptophan. Niacin deficiency may lead to depletion of tryptophan, thereby reducing its availability to form serotonin (4). Thiamine is required for the metabolism of glucose and precursors of GABA. Vitamin B-12, vitamin B-6, and folate are associated with the formation of S-adenosyl-methionine and tetrahydrobiopterin, both ofwhich are required for the metabolism of serotonin and dopamine (5, 6). To our knowledge, no previous studies have examined whether intake of B vitamins may prevent the initial development of PMS. Previous studies of B vitamins and PMS generally have been limited to randomized clinical trials of the efficacy of vitamin B-6 at different doses as a treatment of premenstrual symptoms (7–14). Some (8, 9,15) but not all (11–14) studies have found vitamin B-6 supplementation to reduce the occurrence and severity of symptoms. To our knowledge, no previous studies have assessed the association of PMS or menstrual symptoms with thiamine, niacin, riboflavin, folate, and vitamin B-12 intakes, although some clinical trials have evaluated supplements containing many of these vitamins as treatment ofmenstrual symptoms; the results suggest that B vitamin intake may be beneficial (16–18). We evaluated the association between intakes of thiamine, riboflavin, niacin, vitamin B-6, folate, and vitamin B-12 and the risk of incident PMS in a subset of women participating in the Nurses’ Health Study II (NHS II).

Downloaded from www.ajcn.org by guest on May 20, 2012

Premenstrual syndrome (PMS) is adisorder characterized by physical and psychological symptoms that are manifested during the late luteal phase of the menstrual cycle and end shortly after the onset of menstruation. Although the true prevalence of PMS is unknown, it has been estimated that 15% of women of reproductive age in the United States meet the established clinical criteria for PMS (1). The pathophysiology of PMS remains...