VITAMIN-A INADEQUACY IN SOCIOECONOMICALLY DISADVANTAGED PREGNANT IOWAN WOMEN AS ASSESSED BY THE MODIFIED RELATIVE DOSE-RESPONSE (MRDR) TEST

The vitamin A status of low-income women (n = 57) during the third trimester of pregnancy was assessed by use of the modified relative dose response (MRDR) test. Non-Hispanic White (45), Hispanic (6), Afro-American (5), and Asian (1) women were recruited from public health programs in central Iowa. Serum retinol, beta-carotene, alpha-carotene, lycopene, alpha-tocopherol, and cholesterol concentrations were also measured. Twenty six percent of the study population were found to be in a marginal vitamin A status with MRDR values greater than or equal to 0.03, whereas 9% had values greater than or equal to 0.06. The Hispanic and Afro-American groups seemed to be most at risk, with 50% and 40% (respectively) of the MRDR values greater than or equal to 0.03 and 33% and 20% (respectively) greater than or equal to 0.06. Carotenoid values were similar to those found in women in other like studies, except for the Afro-American group, which had mean values less than half those of the other groups. alpha-Tocopherol concentrations and alpha-tocopherol/cholesterol ratios of all ethnic groups fell in the normal range. The somewhat elevated cholesterol levels found in all groups can largely be attributed to pregnancy. Clearly, this study identifies a portion of the U. S. population at high risk of vitamin A inadequacy.