Significance of postprandial blood concentrations of retinol, retinol-binding protein, and carotenoids when assessing the vitamin A status of children.

The effect of ingesting a breakfast rich in vitamin A on postprandial blood serum concentration of retinol, retinol-binding protein, and carotenoids has been investigated in children between 5 and 8 yr of age. They were divided by age in two groups (5 to 6 and 7 to 8 yr) and then randomly assigned in three groups to be studied cross-sectionally immediately before and at 2 and 4 h after the ingestion of a meal containing 337 micrograms of retinol equivalents (48% as retinol and 52% as carotenoids). The ingestion of breakfast did not alter significantly (p greater than 0.05) the postprandial serum concentrations of retinol, retinol-binding protein; or carotenoids in any of the age groups. These results indicate that up to 4 h the postprandial blood serum concentrations of these parameters are representative of their corresponding basal concentrations. Therefore, in practice and particularly under field survey conditions, the blood samples required to assess the vitamin A status of children can be obtained either fasting or within 4 h after breakfast without altering the results.