Positive Health Online

Abstract

JOHNSON and colleagues, Jean Mayer USDA Human Nutrition Research Center on Aging at tufts University, Boston MA 02111 USA conducted a double-blind study to evaluate beta-carotene and lycopene responses following ingestion of individual and combined doses of beta-carotene (BC) and lycopene.

Background

Methodology

10 healthy men were recruited. On each dosing day, a baseline blood samplse was taken, followed by an oral dose of 60 mg of either all-trans BC or all-trans lycopene or by a combined oral dose of 60 mg each. the participants were tested with each of the 3 doses, which was randomised. Blood was drawn at 1, 3, 5, 7, 9, 12 and 24 hours following dosing. At 2 and 4 weeks following the first dose, the protocol was repeated with the other doses.

Results

Following ingestion of the BC dose, serum levels of BC decreased from baseline at 1 and 3 hours followed by a continuous increase from baseline which was significant at 12 and 24 hours. Levels of serum lycopene increased significantly from baseline at 5 hours following the lycopene dose and thereafter returned to baseline. Ingestion of the combined dose of BC and lycopene resulted in a significant increase in serum levels of both BC and lycopene at 24 hours. The 24-hour area under the curve (AUC) for lycopene was significantly greater when lycopene was ingested with BC rather than alone, although the AUC for BC was unchanged when ingested alone or with lycopene.

Conclusion

These results suggest that ingestion of a combined dose of BC and lycopene improves lycopene absorption in men but has little effect upon BC absorption .

References

Johnson EJ et al. Ingestion by men of a combined dose of beta-carotene and lycopene does not affect the absorption of beta-carotene but improves that of lycopene. J Nutr. 127(9): 1833-7. Sep 1997 .