Evaluation of vitamin B(6) intake and status of 20- to 64-year-old Koreans

BACKGROUND/OBJECTIVES: Recent research regarding vitamin B(6) status including biochemical index is limited. Thus, this study estimated intakes and major food sources of vitamin B(6); determined plasma pyridoxal 5'-phosphate (PLP); and assessed vitamin B(6) status of Korean adults. MATERIALS/METHODS: Three consecutive 24-h diet recalls and fasting blood samples were collected from healthy 20- to 64-year-old adults (n = 254) living in the Seoul metropolitan area, cities of Kwangju and Gumi, Korea. Vitamin B(6) intake and plasma PLP were analyzed by gender and by vitamin B(6) supplementation. Pearson's correlation coefficient was used to determine associations of vitamin B(6) intake and plasma PLP. RESULTS: The mean dietary and total (dietary plus supplemental) vitamin B(6) intake was 1.94 ± 0.64 and 2.41 ± 1.45 mg/day, respectively. Median (50th percentile) dietary intake of men and women was 2.062 and 1.706 mg/day. Foods from plant sources provided 70.61% of dietary vitamin B(6) intake. Only 6.3% of subjects consumed total vitamin B(6) less than Estimated Average Requirements. Plasma PLP concentration of all subjects was 40.03 ± 23.71 nmol/L. The concentration of users of vitamin B(6) supplements was significantly higher than that of nonusers (P < 0.001). Approximately 16% of Korean adults had PLP levels < 20 nmol/L, indicating a biochemical deficiency of vitamin B(6), while 19.7% had marginal vitamin B(6) status. Plasma PLP concentration showed positive correlation with total vitamin B(6) intake (r = 0.40984, P < 0.0001). CONCLUSIONS: In this study, vitamin B(6) intake of Korean adults was generally adequate. However, one-third of subjects had vitamin B(6) deficiency or marginal status. Therefore, in some adults in Korea, consumption of vitamin B(6)-rich food sources should be encouraged.