Black pepper and vegetable oil-based emulsion synergistically enhance carotenoid bioavailability of raw vegetables in humans.

This study demonstrated the combination of black pepper and a canola oil-based emulsion synergistically enhanced carotenoid bioavailability of raw vegetables in humans. In a randomized crossover design, healthy young adults consumed (1) vegetable salad (control), (2) salad with canola oil emulsion (COE), (3) salad with black pepper (BP), and (4) salad with canola oil emulsion and black pepper (COE + BP). COE + BP led to a higher AUC of total plasma carotenoids (p < 0.0005) than the control (6.1-fold), BP (2.1-fold), and COE (3.0-fold). COE + BP increased AUC of plasma lutein, α-carotene, β-carotene, and lycopene by 4.8, 9.7, 7.6, and 5.5-fold than the control, respectively (p < 0.0001). COE + BP produced a significant synergy in increasing both C and AUC of total carotenoids, α-carotene, β-carotene, and lycopene. Moreover, COE + BP produced a stronger enhancement on AUC of total carotenoids, α-carotene, β-carotene, and lycopene in females than in males.