Plasma concentration response to drinks containing β-carotene as carrot juice or formulated as a water dispersible powder

Background Bioavailability of beta-carotene is highly variable and depends on the source, the formulation and other nutritional factors. Objective It was the aim of the study to compare beta-carotene plasma response to beta-carotene dosing with two commercially available drinks, containing beta-carotene from carrot juice or as water dispersible beta-carotene powder. Design In a randomized, parallel group study design, 4 volunteers per group received daily beta-carotene doses of 6-7 or 18-22 mg of either drink over 6 weeks. Blood samples for determination of carotenoid and vitamin A plasma concentrations were collected before supplementation and over the dosing period. Results Apparent steady-state beta-carotene concentrations were attained after 40 days of supplementation. Consumption of the beverage containing beta-carotene as a water dispersible powder resulted in a higher response of beta-carotene plasma concentrations with increments of 3.84 +/- 0.60 mumol/L (p < 0.05, dose: 7.2 mg/d) and 5.04 +/- 0.72 mumol/L (p < 0.05, dose: 21.6 mg/d), respectively, in comparison to the carrot juice-based drink. with increments of 0.42 +/- 0.33 mumol/L (dose: 6 mg/d) and 1.71 +/- 0.55 mumol/L (dose: 18 mg/d), respectively. beta-carotene was cleared from the plasma with an apparent half-life of 6-11 days. Plasma concentrations of alpha-carotene, beta-cryptoxanthin, lutein, zeaxanthin, and lycopene remained almost unchanged, whereas retinol plasma concentrations increased slightly. By contrast, with the exception of elevated 13-cis-retinoic acid in one group (21.6 mg/d, water dispersible powder), the concentrations of all-trans-retinoic acid, and the oxo-derivatives or retinoic acid were not significantly affected by beta-carotene supplementation. Conclusions The results confirm that the relative bioavailability of beta-carotene depends largely on the source of beta-carotene and demonstrate the superior bioavailability of beta-carotene powder in comparison to that in carrot juice.