INCOME AND RACIAL PATTERNS OF DIETARY VITAMIN-C INTAKE AMONG BLACK-AND-WHITE GIRLS

The authors examined the influence of income and race on mean dietary vitamin C intake and the risk of dietary vitamin C intake at levels be low the recommended dietary allowance (RDA). They performed a cross-se ctional analysis of 2,032 black and white 9- and 10-year-old females, from a wide range of income groups, who participated in the National H eart, Lung, and Blood Institute Growth and Health Study. Mean intake o f vitamin C, exclusive of vitamin supplements and determined by 3-day diet records, exceeded the RDA of 45 milligrams per day for that age g roup in all racial and income categories. The investigators found that annual household income was directly associated with mean dietary vit amin C intake (P < 0.0001) and that blacks had higher mean dietary vit amin C intakes than whites (P < 0.01). Among both blacks and whites, h ousehold income and risk of below-RDA vitamin C intake were inversely correlated, but this trend was statistically significant for blacks on ly (P < 0.05). Except for the lowest level income group (less than $10 ,000 per year), black girls from households with incomes less than $30 ,000 per year were at increased risk for below-RDA vitamin C intake (r elative risk = 1.93 in the $10,000-$19,999 per year group and 1.63 in the $20,000-29,999 per year group, P < 0.05), compared with black girl s in the highest income category. One-quarter of white girls overall a nd more than 30 percent of white girls in the lowest two income groups had below-RDA vitamin C intakes. If the findings are generalizable, t hey underscore the importance of public health programs to address the adequacy of dietary vitamin C intake among preadolescent black and wh ite females.