Vitamin E status of 20- to 59-year-old adults living in the Seoul metropolitan area of South Korea

BACKGROUND/OBJECTIVES: Vitamin E is a fat-soluble vitamin and functions primarily as a lipid antioxidant. Inadequate vitamin E status may increase risk of several chronic diseases. Thus, the objectives of this study were to estimate intake and plasma concentration of each tocopherol and to evaluate vitamin E status of Korean adults. SUBJECTS/METHODS: Three consecutive 24-h food recalls and fasting blood samples were collected from healthy 20- to 59-y-old adults (33 males and 73 females) living in the Seoul metropolitan area, South Korea. ${\alpha}$-, ${\beta}$-, ${\delta}$-, and ${\gamma}$-tocopherol intakes and plasma concentrations of tocopherols (${\alpha}$-, ${\delta}$-, and ${\gamma}$- tocopherol) were analyzed by gender. RESULTS: Dietary vitamin E and total vitamin E intake (dietary plus supplemental vitamin E) was $17.68{\pm}14.34$ and $19.55{\pm}15.78mg$ ${\alpha}$-tocopherol equivalents, respectively. The mean daily ${\alpha}$-tocopherol, and ${\gamma}$-tocopherol intakes were $3.07{\pm}2.27mg$ and $5.98{\pm}3.74mg$, respectively. Intakes of total vitamin E and each tocopherol of males were significantly higher than those of females (P < 0.05). Plasma ${\alpha}$-tocopherol concentration was $15.45{\pm}10.16$ of males and $15.00{\pm}4.54{\mu}mol/L$ of females, respectively. There were no significant differences in plasma tocopherol concentrations by gender ($P{\geq}0.05$). Plasma ${\alpha}$-tocopherol was negatively correlated with ${\gamma}$-tocopherol intake (P < 0.05). Twenty-three percent of the subjects had plasma ${\alpha}$-tocopherol concentrations < $12{\mu}mol/L$ indicating a biochemical deficiency of vitamin E. Approximately 8% and 9% of these participants had plasma ${\alpha}$-tocopherol:total lipid ratio less than $1.59{\mu}mol/mmol$ and plasma ${\alpha}$-tocopherol:total cholesterol ratio less than $2.22{\mu}mol/mmol$, respectively, which are also indicative of vitamin E deficiency. CONCLUSIONS: Vitamin E intakes of Korean adults were generally adequate with the Korean Dietary Reference Intakes for vitamin E. However, ${\alpha}$-tocopherol intake was lower than that reported in other countries, and 23% of the subjects in the current study were vitamin E deficient based on plasma ${\alpha}$-tocopherol concentrations.