The effects of carrot juice consumption on serum alpha- and betacarotene, total carotenoid and retinol levels were studied in 10 adulted volunteers, age 23-48 years. Five subjects consumed 16 ounces of juice per day for 7 days and then 8 ounces every other day for the next 7 days. Another group of 5 subjects consumed 16 ounces of juice per day for 7 days and then received no carrot juice for the next 7 days. Blood serum collected from both groups at the start of the study and after day 7 and day 14 was analyzed by HPLC and spectrophotometry for carotenoid and retinol concentration. When consumption of carrot juice was continuous, alpha-carotene and total carotenoids increased at 1 week and stabilized, while beta-carotene continued to increase over the course of the 2 weeks. When carrot juice consumption occurred for 1 week and was then terminated, alpha-and beta-carotene rose at 1 week and then stabilized, while total carotenoids rose at 1 week and returned to baseline level after the week of withdrawal. Serum retinol levels did not change for either group throught the study period.
Bibliographical noteFunding Information:
The authors wish to acknowledge this work as contribution #2356 of the University of Rhode Island Agricultural Experiment Station. The work was also supported in part by a grant from the University of Rhode Island Agricultural Experiment Station. The authors would also like to thank Mr. Philip Pivarnik for technical assistance during the course of this research and the assistance of Dr. Henry Dymsza in the preparation of this manuscript. The generous gift of samples of carrot juice provided by Mr. David Lane, President of the Escondido Juice Company is gratefully acknowledged.
All Science Journal Classification (ASJC) codes
- Endocrinology, Diabetes and Metabolism
- Nutrition and Dietetics