Lycopene and β-carotene are bioavailable from lycopene ‘red’ carrots in humans

Abstract

Objective: The purpose of this study was to determine if lycopene and b-carotene are bioavailable from lycopene red carrots and if lycopene absorption is affected by carrot fiber. Design: Two crossover studies in humans attempted to compare the relative bioavailability of lycopene and b-carotene from tomato paste to a genetically selected lycopene red carrot during chronic feeding. Each study contained three treatment groups. The vehicle of administration was muffins. Intervention and methods: Study 1 (n¼9) used white carrots (0 mg lycopene/day), red carrots (5 mg/day), and tomato paste (20 mg/day). Study 2 (n¼10) used red carrots (2.6 mg/day), tomato paste (5 mg/day), and tomato paste plus white carrots (5 mg/day). Each intervention lasted 11 days with a 10-day washout period between treatments. Serum lycopene and bcarotene were measured by HPLC. Results: Statistical analysis indicated a significant effect of muffin type in study 1 (Po0.001), and a significant treatment by sequence interaction in study 2 (P¼0.04). The response to increasing amounts of lycopene is linear at the levels fed in these studies (r¼0.94). The data suggest that maintenance of serum lycopene concentrations at 0.3 mmol/l occurs at about 2 mg/day of lycopene from mixed dietary sources and a serum plateau occurs at Z20 mg/day. Conclusions: These results show that lycopene and b-carotene are bioavailable from red carrots and lycopene absorption seems to be affected by carrot fiber. Making inferences from both studies, the lycopene in the red carrot is about 44% as bioavailable as that from tomato paste. Red carrots provide an alternative to tomato paste as a good dietary source of lycopene and also provide bioavailable b-carotene.

Intestinal absorption of dietary carotenoids

“…The plasma response after the ingestion of nutritional doses of carotenoids as well as the carotenoid uptake by Caco-2 from physiological concentrations of carotenoids (up to ca. 2 lM) respond linearly to the carotenoid dose [67,68,79]. Therefore, with carotenoid intakes at nutritional levels the luminal carotenoid concentration falls in the linear response range, well below the onset of carotenoid transport saturation which occurs at 15-20 lM [67,68].…”

Thermal processing of carrots: Lycopene stability and isomerisation with regard to antioxidant potential

“…in guava (Bruno & Wildman, 2001;Nguyen & Schwartz, 1999). Lycopene bioavailability is from Nutri Red-carrots and tomatoes comparable (Horvitz, Simon, & Tanumihardjo, 2004). According to current literature data, a combined consumption of different carotenoids may provide synergistic health promoting effects (Stahl et al, 1998).…”

Tissue-specific accumulation of carotenoids in carrot roots

“…Moreover, they occur in non-photosynthetic tissues of some Xowers and fruits enhancing attractiveness to pollinators and animals dispersing seeds. Carrot storage root is also a rich source of carotenoids, which are bioavailable to animals and human beings (Horvitz et al 2004). It is well known that -and -carotene can be converted to vitamin A (Olsen 1989) and carrot is one of the main sources of these compounds in the US diet (Rubatzky et al 1999).…”