Plasma carotenoid concentrations before and after supplementation with a carotenoid mixture.

Plasma carotenoid concentrations were determined by HPLC in 11 individuals consuming low-carotenoid diets and after taking a carotenoid supplement. Subjects first consumed low-carotenoid diets for 2 wk, then supplemented these diets daily with 8.5 mg beta-carotene, 3.5 mg alpha-carotene, and 0.5 mg lycopene, from natural sources for 4 wk. Serum cholesterol, triglycerides, and lipoproteins were determined before and after supplementation. After 2 wk on the low-carotenoid diet, plasma concentrations of the three carotenoids fell to approximately 60% of baseline values. One week after supplementation, alpha- and beta-carotene concentrations returned to baseline and by the end of the supplementation period they were significantly higher than baseline values (P < 0.05). Lycopene concentrations increased only slightly. Serum lipids did not change significantly. Overall, plasma concentrations of these carotenoids reflect the amount provided by the supplement. This is the first study reporting increments of serum carotenoids, other than beta-carotene, after supplementation.