Tomato consumption increases lycopene isomer, concentrations in breast milk and plasma of lactating women

Objective To compare plasma and milk lycopene concentrations and the changes in lycopene isomer patterns in lactating women before and after a 3-day dietary intervention with fresh or processed tomato products. Design Randomized prospective trial. Subjects 24 lactating women, 4 to 12 weeks postpartum, aged 22 to 39 years. Intervention Subjects initially consumed a low-lycopene diet for 7 days (washout period) and then were randomly assigned to one of 3 dietary groups (n=8 per group) without any other sources of lycopene: control (low-lycopene), fresh tomatoes, or processed tomato sauce. Subjects in each of the tomato groups consumed approximately 50 mg total lycopene over 3 days. Outcome measures Before and after dietary intervention, plasma and breast milk samples were obtained for high-performance liquid chromotography analysis of lycopene and its geometric isomers (all-trans, 5-cis, all other cis, and total lycopene). Statistical analysis Descriptive statistics, analysis of variance to test for differences among intervention groups, and Spearman's correlation coefficients to test for blood-milk relationships. Results Plasma total lycopene and lycopene isomer concentrations increased in the fresh and processed tomato group but not in the low-lycopene control group during the study. Milk total and cis- and trans-lycopene concentrations (unadjusted for fat) increased in the processed tomato group but did not change in the fresh tomato group. In the control group, milk total and trans-lycopene decreased. Milk total lycopene concentrations were not significantly different from baseline in any group when adjusted for fat content of milk. Applications The results of this study indicate that consumption of a "standard size portion" of tomato products increases plasma and milk lycopene concentrations in lactating, women and, therefore, could increase the lycopene status of nursing infants. For dietary recommendations during lactation, the results suggest that consumption of tomato sauce increases milk lycopene concentrations more effectively than consumption of fresh tomatoes.