Relationship between dietary intake and plasma concentrations of carotenoids in premenopausal women: application of the USDA-NCI carotenoid food-composition database.

The diet-plasma relationships for carotenoids were examined in a group of 98 nonsmoking premenopausal women who participated in the cross-sectional phase of the National Cancer Institute (NCI)-US Department of Agriculture (USDA) diet study on alcohol-hormone metabolism, 1988-90. With use of the newly developed USDA-NCI carotenoid food-composition database, the mean daily intakes of carotenoids were significantly higher when estimated from the food-frequency questionnaire (FFQ) than from the 7-d diet records. Lycopene (mean = 0.58 mmol/L), lutein plus zeaxanthin (mean = 0.46 mmol/L), and beta-carotene (mean = 0.34 mmol/L) were the major plasma carotenoids. After adjustment for body mass index, energy and alcohol intakes, and total plasma cholesterol concentration, the following significant correlation (P < 0.05) were observed between the diet record and the FFQ-estimated carotenoid intakes and their respective plasma concentrations: alpha-carotene (r = 0.58 vs 0.49), beta-carotene (r = 0.51 vs 0.49), beta-cryptoxanthin (r = 0.49 vs 0.36), lutein plus zeaxanthin (r = 0.31 vs 0.37), lycopene (r = 0.50 vs 0.26), and total carotenoids (r = 0.57 vs 0.49). These data indicate that plasma carotenoid concentrations are reflective of dietary intake, but the magnitude of the correlation varies depending on the specific carotenoid and on the dietary assessment tool.