Suboptimal maternal and cord plasma pyridoxal 5' phosphate concentrations are uncommon in a cohort of Canadian pregnant women and newborn infants.

Vitamin B6 is important in fetal development, but little is known of the vitamin B6 status of pregnant women and newborns in North America and potential modifying factors. This prospective study determined maternal and cord plasma concentrations of pyridoxal 5' phosphate (PLP; an indicator of vitamin B6 status) in a convenience sample of 368 Canadian pregnant women and their newborns. The association of maternal intake of vitamin B6 and fetal genetic variants with cord plasma PLP and homocysteine concentrations was also examined. Dietary and supplemental intakes of vitamin B6 were assessed in early and mid to late pregnancy. PLP concentrations were measured in maternal plasma in early pregnancy and at delivery, and in cord plasma. Six fetal variants of the MTHFR and CßS genes were assessed for their association with cord plasma PLP and homocysteine concentrations. Geometric mean (95% CI) PLP concentrations were 107 (98, 116) nmol/L in early pregnancy and 58 (53, 62) nmol/L at delivery, respectively, and 296 (275, 319) nmol/L in cord blood (p < .0001). During early pregnancy and at delivery, 3.6% and 5.5% of women had plasma PLP concentrations <20 nmol/L, respectively. Ninety eight percent of the women with supplemental B6 intake of at least the recommended dietary allowance had PLP concentrations >20 nmol/L. Fetal genetic variants were not associated with cord PLP and homocysteine concentrations. Vitamin B6 deficiency is uncommon in a cohort of Canadian pregnant women due largely to prevalent vitamin B6 supplement use.

Very low adequacy of micronutrient intakes by young children and women in rural Bangladesh is primarily explained by low food intake and limited diversity.

Documentation of micronutrient intake inadequacies among developing country populations is important for planning interventions to control micronutrient deficiencies. The objective of this study was to quantify micronutrient intakes by young children and their primary female caregivers in rural Bangladesh. We measured 24-h dietary intakes on 2 nonconsecutive days in a representative sample of 480 children (ages 24-48 mo) and women in 2 subdistricts of northern Bangladesh by using 12-h weighed food records and subsequent 12-h recall in homes. We calculated the probability of adequacy (PA) of usual intakes of 11 micronutrients and an overall mean PA, and evaluated dietary diversity by counting the total number of 9 food groups consumed. The overall adequacy of micronutrient intakes was compared to dietary diversity scores using correlation and multivariate regression analyses. The overall mean prevalence of adequacy of micronutrient intakes for children was 43% and for women was 26%. For children, the prevalence of adequate intakes for each of the 11 micronutrients ranged from a mean of 0 for calcium to 95% for vitamin B-6 and was <50% for iron, calcium, riboflavin, folate, and vitamin B-12. For women, mean or median adequacy was <50% for all nutrients except vitamin B-6 and niacin and was <1% for calcium, vitamin A, riboflavin, folate, and vitamin B-12. The mean PA (MPA) was correlated with energy intake and dietary diversity, and multivariate models including these variables explained 71-76% of the variance in MPA. The degree of micronutrient inadequacy among young children and women in rural Bangladesh is alarming and is primarily explained by diets low in energy and little diversity of foods.

Vitamin B6 is associated with depressive symptomatology in Massachusetts elders.

OBJECTIVE: We examined the cross-sectional relationship between dietary vitamin B6 and plasma pyridoxyl-5'-phosphate concentrations (PLP) with depressive symptomatology among a representative sample of 618 elderly Caribbean Hispanics, and a neighborhood based comparison group of 251 non-Hispanic white (NHW) older adults in Massachusetts. METHODS: Depressive symptomatology was assessed with the Center for Epidemiologic Studies Depression Scale (CES-D). 41% of Hispanics and 22.6% of NHWs had CES-D scores greater than 16, indicating depressive caseness. Dietary intake was calculated from a semi-quantitative food frequency questionnaire (FFQ) designed for this population. RESULTS: PLP was significantly associated with CES-D score and depressive caseness in the total sample and in non-supplement users. Deficient levels of plasma PLP (plasma PLP < 20 nmol/L) approximately doubled the likelihood of depressive caseness. Total intake (diet + supplement) of vitamin B(6) was not associated with these outcomes. However, dietary vitamin B(6) was significantly associated with CES-D score and depressive caseness. CONCLUSION: Longitudinal studies are needed to clarify the direction of causality between vitamin B6 and depressive symptoms.

Vitamin B6 and coronary artery disease. Epidemiological observations and case studies.

The finding of low plasma pyridoxal-5'-phosphate levels in patients suffering from myocardial infarction has been construed as possible evidence for the pathogenetic role that vitamin B6 deficiency may play in causing premature ischaemic heart disease. However, the presence of normal plasma pyridoxal-5'-phosphate levels in patients with angiographic evidence of coronary artery narrowing but with no previous infarctions prompted the investigation of possible short-term alterations in plasma pyridoxal-5'-phosphate levels during the acute phase of myocardial infarction. In the follow-up of 30 patients with acute myocardial infarction, all of them showed a continuous decrease of approximately 45% in plasma pyridoxal-5'-phosphate levels during the acute phase. These levels subsequently returned back to normal before discharge from hospital. A large number of volunteers from an ethnic group known to have a very low incidence of ischaemic heart disease were found to have both significantly lower total cholesterol and plasma pyridoxal-5'-phosphate levels than a Caucasian group in the same geographic area which is known to have a high incidence of ischaemic heart disease. These findings therefore do not support the contention that vitamin B6 deficiency may be a risk index for ischaemic heart disease.