Vitamin A status of 20- to 59-year-old adults living in Seoul and the metropolitan area, Korea

Dietary intakes and plasma concentrations of retinol and carotenoids were estimated in assessing the vitamin A status of Korean adults living in Seoul and the metropolitan area. Three consecutive 24-h food recalls were collected from 106 healthy subjects (33 males and 73 females) aged 20-59 years. Fasting blood samples of the subjects were obtained and plasma retinol and carotenoids were analyzed. The daily vitamin A intakes ($mean{\pm}SD$) were $887.77{\pm}401.35{\mu}g $ retinol equivalents or $531.84{\pm}226.42{\mu}g$ retinol activity equivalents. There were no significant differences in vitamin A intakes among age groups. The retinol intake of subjects was $175.92{\pm}129.87{\mu}g/day$. The retinol intake of the subjects in their 50's was significantly lower than those in their 20's and 30's (P<0.05). Provitamin A carotenoid intakes were $3,828.37{\pm}2,196.29{\mu}g/day$ ${\beta}$-carotene, $472.57{\pm}316.68{\mu}g/day$ ${\alpha}$-carotene, and $412.83{\pm}306.46{\mu}g/day$ ${\beta}$-cryptoxanthin. Approximately 17% of the subjects consumed vitamin A less than the Korean Estimated Average Requirements for vitamin A. The plasma retinol concentration was $1.22{\pm}0.34{\mu}mol/L$. There was no significant difference in plasma retinol concentrations among age groups. However, the concentrations of ${\beta}$-carotene, lycopene, and lutein of subjects in their 50's were significantly higher than those of in their 20's. Only one subject had a plasma retinol concentration < $0.70{\mu}mol/L$ indicating marginal vitamin A status. Plasma retinol concentration in 30% of the subjects was 0.70- < $1.05{\mu}mol/L$, which is interpreted as the concentration possibly responsive to greater intake of vitamin A. In conclusion, dietary intakes and status of vitamin A were generally adequate in Korean adults examined in this study.