Dietary Intake of Vitamin B-6, Plasma Pyridoxal 5 ';-Phosphate, and Homocysteine in Puerto Rican Adults

作者：Ye Xingwang; Maras Janice E; Bakun Peter J; Tucker Katherine L^*

来源：Journal of the American Dietetic Association, 2010, 110(11): 1660-1668.

DOI：10.1016/j.jada.2010.08.006

Background Vitamin B-6 is an important cofactor in many metabolic processes. However, vitamin B-6 intake and plasma status have not been well studied in the Puerto Rican population, a group with documented health disparities.
Objective To assess dietary intake of vitamin B-6, food sources, and plasma status of pyridoxal 5';-phosphate (PLP), and their associations with plasma homocysteine in 1,236 Puerto Rican adults, aged 45 to 75 years, living in the greater Boston area.
Design Baseline data were analyzed cross-sectionally.
Method Questionnaire data were collected by home interview. Dietary intake was assessed with a semiquantitative food frequency questionnaire. Plasma PLP and homocysteine were assayed from blood samples collected in the home.
Results The mean daily intake of vitamin B-6 was 2.90 +/- 1.28 mg for men and 2.61 +/- 1.29 mg for women (P<0.001). Approximately 11% were deficient (PLP <4.94 ng/mL [PLP <20 nmol/L]) and another 17% insufficient (PLP >= 4.94 but <7.41 ng/mL [PLP >= 20 but <30 nmol/L]). Household income below the poverty threshold, physical inactivity, and current smoking were significantly associated with lower plasma PLP (P<0.05). Food groups contributing most to vitamin B-6 intake included ready-to-eat cereals, poultry, rice, potatoes, and dried beans. However, only intake of ready-to-eat cereals and use of supplements with vitamin B-6 were significantly associated with plasma PLP sufficiency (>= 7.41 vs <7.41 ng/mL [PLP >= 30 vs <30 nmol/L], P<0.01). Both vitamin B-6 intake and PLP were significantly associated with plasma total homocysteine (P<0.001). The association between PLP and homocysteine remained statistically significant after further adjustment for plasma vitamin B-12 and folate (P=0.028).
Conclusions Given the known importance of vitamin B-6 to health, the high prevalence of low vitamin B-6 status in this Puerto Rican population is of concern. Further work is needed to clarify the potential role that insufficient vitamin B-6 may have in relation to the observed health disparities in this population. J Am Diet Assoc. 2010;110:1660-1668.

• 出版日期2010-11
• 单位东北大学