The objective of the present study was to evaluate intakes and serum levels of vitamin A, vitamin E, and related compounds in a cohort of maternal–infant pairs in the Midwestern USA in relation to measures of health disparities. Concentrations of carotenoids and tocopherols in maternal serum were measured using HPLC and measures of socio-economic status, including food security and food desert residence, were obtained in 180 mothers upon admission to a Midwestern Academic Medical Center labour and delivery unit. The Kruskal–Wallis and independent-samples t tests were used to compare measures between groups; logistic regression models were used to adjust for relevant confounders. P < 0·05 was considered statistically significant. The odds of vitamin A insufficiency/deficiency were 2·17 times higher for non-whites when compared with whites (95 % CI 1·16, 4·05; P = 0·01) after adjustment for relevant confounders. Similarly, the odds of being vitamin E deficient were 3·52 times higher for non-whites (95 % CI 1·51, 8·10; P = 0·003). Those with public health insurance had lower serum lutein concentrations compared with those with private health insurance (P = 0·05), and living in a food desert was associated with lower serum concentrations of β-carotene (P = 0·02), after adjustment for confounders. Subjects with low/marginal food security had higher serum levels of lutein and β-cryptoxanthin compared with those with high food security (P = 0·004 and 0·02 for lutein and β-cryptoxanthin). Diet quality may be a public health concern in economically disadvantaged populations of industrialised societies leading to nutritional disadvantages as well.

Dietary intervention may alter the insulin-like growth factor (IGF) system and thereby cancer risk. In a qualitative review, eleven of twenty studies showed a link between one or more carotenoids, vegetable or fruit intake and the IGF system, however, with partly contrary findings, such that no firm conclusion can be drawn. Therefore, we evaluated associations between serum carotenoid concentrations or the intake of fruits and vegetables with IGF-1, IGF binding protein (BP)-3 and their molar ratio (IGF-1:IGFBP-3) within the Third National Health and Nutrition Examination Survey (NHANES III, 1988–1994). In our analysis, we included 6061 NHANES III participants and used multivariable-adjusted linear regression models. IGF-1 concentrations were significantly positively associated with serum concentrations of lycopene, β-carotene, α-carotene, β-cryptoxanthin and lutein/zeaxanthin in men and women. Statistically significant positive associations were observed for serum concentrations of α-carotene and lutein/zeaxanthin and intake of fruits with serum IGFBP-3 concentrations in women, but not in men. The IGF-1:IGFBP-3 molar ratio was significantly positively associated with serum concentrations of lycopene, β-carotene and α-carotene in men and with β-carotene in women. In conclusion, dietary interventions with carotenoids, fruits and vegetables may affect the IGF system, although the direction of these effects is currently unclear.