Vitamin B6 status of women suffering from premenstrual syndrome.

The vitamin B6 status of women suffering from premenstrual symptoms (PMS, n = 19) and a group of matched controls (n = 19) has been investigated. The women volunteering in the study were selected on strictly defined criteria. Several biochemical parameters of the metabolism of vitamin B6 and tryptophan were studied in blood and urine samples during a full menstrual cycle. No significant differences in plasma pyridoxal and pyridoxal-5'-phosphate (PLP) concentrations, the holo and total EGOT activity, the erythrocyte pyridoxine kinase activity and the urinary 4-pyridoxic acid excretion between the two groups were observed. The excretion of the tryptophan metabolites xanthurenic acid (XA) and 8-methyl-xanthurenic acid (MXA), before as well as after an oral tryptophan load, tended to be higher for the PMS group. Each of the groups showed a significant cyclic variation during the menstrual cycle in the holo and total EGOT activities and in the excretion of XA and MXA before as well as after an oral tryptophan load. It is concluded that PMS is not related to a 'cyclic' vitamin B6 status. The slight differences observed for tryptophan metabolism between the PMS and the control group deserve further study.