One-half of Korean adults studied had marginal vitamin B12 status assessed by plasma vitamin B12.

Information is limited on the current vitamin B12 status of South Koreans, including the results of biochemical indices. The objective of this study was to assess vitamin B12 status with vitamin B12 intake, major food sources, and plasma vitamin B12 concentration in Korean adults. We hypothesized that vitamin B12 intake and status would be different between sex and age groups. Three consecutive 24-hour recalls and fasting blood samples were obtained from healthy 20- to 64-year-old adults (N=141). The dietary vitamin B12 intake of the men (10.77±6.11 μg/d) was significantly higher than that of the women (7.93±5.01 μg/d). The mean dietary vitamin B12 intake was significantly lower in the subjects aged 20-29 years than in the subjects aged 50-64 years. Only 2.1% of the subjects consumed less vitamin B12 than the estimated average requirement for Koreans. The top 4 major food sources of vitamin B12 were seafood, which provided 35.36% of the dietary vitamin B12 intake. There was no significant difference in plasma vitamin B12 concentration between sex and among age groups. Approximately 17% of total subjects had a plasma vitamin B12 concentration <125 pmol/L, indicating vitamin B12 deficiency, and 36.2% had marginal vitamin B12 status (125 to <250 pmol/L). The reported vitamin B12 intake was affected by both sex and age. However, plasma vitamin B12 concentration did not differ between sex and among age groups. One-half of the subjects had marginal vitamin B12 status using plasma vitamin B12.