Plant Profiler

Carrot (Daucus carota)

Daucus carota
Synonyms / Common Names / Related Terms
Alpha-carotene, anthocyanins, beta-carotene, carotenoid, carotenoids, carrot cake, carrot jam, carrot juice, carrot puree, carrot soup, Daucus carota, dietary fiber, grated carrots, lycopene, lycopene red carrots, myristicin, purple carrots, red carrots, Umbelliferae (family), vitamin A, white carrots.

Mechanism of Action


  • Constituents: Carrots contain carotenes, especially alpha- and beta-carotenes, vitamin A, and dietary fiber.13,8,14,15,2 Red carrots also contain lycopene.15
  • Antioxidant activity: In several clinical trials, ingestion of carrot juice significantly increased carotenoid levels in lipoproteins and feces, but only slightly increased antioxidant capacity.9,10,11 One study did find that carrot juice significantly reduced oxidative base damage.12 It has been recommended that future antioxidant studies be randomized controlled trials instead of cross-over trials.16
  • Estrogenic properties: In an in vitro study, active extracts/fractions/compounds from Daucus carota exhibited estrogenic activity.5
  • Gastrointestinal effects: In two clinical trials, consumption of 19-33g of carrots per day increased gastrointestinal transit time, fiber intake, and fecal bulking/weight, dry matter, fiber, and protein.6,2 Another clinical trial that supplemented the subjects' diet with powdered carrot fiber found that it did not significantly modify colonic motor effects, other than to initiate high amplitude propagated contractions at a more distal location than the subjects' habitual diet.1 In a clinical trial in children, a carrot-rice based rehydration solution significantly decreased the duration of diarrhea, mean fecal output, and mean fluid intake compared to two conventional glucose-based rehydration solutions.7
  • Immune effects: Watzl et al. conducted two clinical studies to assess the effect of dietary carotenoids from vegetable supplementation on immune function after a low-carotenoid diet.17,18 In the earlier study, diet supplementation was two weeks of tomato juice, followed by two weeks of carrot juice, then two weeks of spinach powder.18 The carrot juice did not affect immune function, a result that may have been skewed due to the previous two weeks of tomato juice consumption. In the later study, carrot juice consumption alone after a low-carotenoid diet did not affect immune system function.17
  • Insulin effects: In a clinical trial of 10 healthy approximately 40 year-old males, consumption of 200g of processed and cooked carrots significantly lowered glucose and insulin/C-peptide responses.4


  • Kurilich et al. conducted a pharmacokinetics study using purple carrots.19 The subjects consumed 250g raw (463mcM of anthocyanins: 400mcM acylated, 63mcM nonacylated), 250g cooked (357mcM of anthocyanins: 308.5mcM acylated, 48.5mcM nonacylated), and 500g cooked (714mcM of anthocyanins: 617mcM acylated, 97mcM nonacylated) carrots. According to the authors, four of the five carrot anthocyanins were found intact in plasma 30 minutes after carrot consumption and peaked between 1.5 and 2.5 hours. Acylation of anthocyanins resulted in an 11- to 14-fold decrease in anthocyanin recovery in urine and an 8- to 10-fold decrease in anthocyanin recovery in plasma. Cooking increased the recovery of nonacylated anthocyanins but not acylated anthocyanins. Large dose size significantly reduced recovery of both acylated and nonacylated anthocyanins, suggesting saturation of absorption mechanisms.
  • In another clinical trial, Thurmann et al. investigated the bioavailability of beta-carotene from carrot juice and a water dispersible beta-carotene powder.20 According to the authors, apparent steady-state beta-carotene concentrations were attained after 40 days of supplementation. Consumption of the beverage containing beta-carotene powder resulted in a higher response of beta-carotene plasma concentrations with increments of 3.84 ± 0.60mcM/L (p<0.05, dose: 7.2mg per day) and 5.04 ± 0.72mcM/L (p<0.05, dose: 21.6mg per day), respectively, in comparison to the carrot juice-based drink with increments of 0.42 ± 0.33mcM/L (dose: 6mg per day) and 1.71 ± 0.55mcM/L (dose: 18mg per day), respectively. Beta-carotene was cleared from the plasma with an apparent half-life of six to 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 (21.6mg per day, 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.
  • Horovitz et al. conducted a bioavailability study of the lycopene in red carrots.15 In the first of two cross-over studies, subjects (N=9) ingested muffins containing white carrots (0mg lycopene per day), red carrots (5mg per day), and tomato paste (20mg per day). Study 2 (N=10) used muffins containing red carrots (2.6mg per day), tomato paste (5mg per day), and tomato paste plus white carrots (5mg per day). Each intervention lasted 11 days with a 10-day washout period between treatments. According to the authors, statistical analysis indicated a significant effect of muffin type in study 1 (p<0.001), and a significant treatment by sequence interaction in study 2 (p=0.04). The response to increasing amounts of lycopene is linear at the levels fed in these studies (r=0.94). The data suggest that maintenance of serum lycopene concentrations at 0.3mcM/L occurs at about 2mg per day of lycopene from mixed dietary sources and a serum plateau occurs at ≥20mg per day.
  • Cardinault et al. conducted a study to test the effect of age on carotenoid bioavailability.21 According to the authors, eight young (20-35 years) and eight older (60-75 years) healthy adults ingested three different meals containing 40g triacylglycerols and vegetable sources of carotenoids. These sources were either 188g carrot puree (30mg beta-carotene), or 61g tomato puree (30mg lycopene), or 260g cooked chopped spinach (30mg lutein). Triacylglycerols and carotenoids were assayed in chylomicrons collected for nine hours postprandially. There was no major effect of age on the postprandial chylomicron:triacylglycerol response (0-9 hour area under the curve (AUC)). There was no major effect of age on the postprandial chylomicrons all-trans beta-carotene, cis beta-carotene, alpha-carotene, and lutein responses. Adjustment of these responses by the chylomicron:triacylglycerol responses did not reveal any age effect. While there was no significant effect of age on the chylomicron:lycopene response, the chylomicron:triacylglycerol-adjusted lycopene response was significantly lower (-40%) in the older than in the younger subjects (p<0.04). The cis-trans ratios of chylomicron:betacarotene were not significantly different between the old and the young subjects. There was no significant effect of age on the ratio of chylomicrons:retinyl-palmitate to the sum of alpha-carotene and beta-carotene measured after the carrot meal.
  • Tyssandier et al. conducted another study to assess the intestinal absorption of cartenoids.22 According to the authors, 10 healthy men were intragastrically fed three liquid test meals differing only in the vegetable added three weeks apart and in a random order. They contained 40g sunflower oil and mashed vegetables as the sole source of carotenoids. Tomato puree provided 10mg lycopene, chopped spinach (10mg lutein), and carrot puree (10mg beta-carotene). All-trans and cis carotenoids were assayed in stomach and duodenal contents, in the fat and aqueous phases of those contents, and in chylomicrons. The cis-trans beta-carotene and lycopene ratios did not significantly vary in the stomach during digestion. Carotenoids were recovered in the fat phase present in the stomach during digestion. The proportion of all-trans carotenoids found in the micellar phase of the duodenum was as follows (means ± SE): lutein (5.6 ± 0.4%), beta-carotene (4.7 ± 0.3%), and lycopene (2.0 ± 0.2%). The proportion of 13-cis beta-carotene in the micellar phase was significantly higher (14.8 ± 1.6%) than that of the all-trans isomer (4.7 ± 0.3%). There was no significant variation in chylomicron lycopene after the tomato meal; however, there was significant increase in chylomicron beta-carotene and lutein after the carrot and the spinach meals, respectively. There is no significant cis-trans isomerization of beta-carotene and lycopene in the human stomach.
  • Kirkman et al. compared the urinary lignan and isoflavonoid excretion in 11 men and nine women consuming four nine-day controlled experimental diets: basal (vegetable free), carotenoid vegetable (carrot and spinach), cruciferous vegetable (broccoli and cauliflower), and soy (tofu and textured vegetable protein product).23 According to the authors, three-day urine collections (days 7-9) were analyzed for lignans and isoflavonoids with use of isotope-dilution gas chromatography-mass spectrometry. Urinary excretion of the lignans enterodiol and enterolactone was higher in the carotenoid and cruciferous vegetable diets than in the basal diet (p=0.0001), suggesting that these vegetables may provide a source of mammalian lignan precursors. Urinary excretion of the isoflavonoids equol, O-desmethylangolensin, daidzein, and genistein was higher when subjects consumed soy diets than when they consumed the other test diets (p<0.02). Gender differences in lignan excretion were observed. Men excreted more enterolactone (p=0.006) and less enterodiol (p=0.013) than women, implying a gender difference in colonic bacterial metabolism of lignans. There was no effect of gender on isoflavonoid excretion.
  • In a pharmacokinetics study, Agte et al. compared consumption of micronutrients through vegetables to consumption of micronutrients through tablet supplementation.3 The study was a short-term (0-4 hour) response (area under the curve, AUC) of single dose of 7.9mg beta-carotene and 130mg ascorbic acid through a spinach-carrot meal against the standard meal without green leafy vegetables plus 10mg beta-carotene and 150mg ascorbic acid tablets. There were two groups of four young volunteers each. The authors report in the second trial of three weeks' supplementation, five groups of young adults (N=40) were given either 100g green leafy vegetables daily alone or with tablets of vitamin E (100mg daily) or C (100mg daily) or more oil (5g daily) or non-green leafy vegetables meal with tablet of beta-carotene (10mg daily). According to the authors, hemoglobin, plasma beta-carotene, zinc, vitamin C, glucose, and triglycerides were measured. In a postprandial response, AUC were comparable in both green leafy vegetables and standard meals for beta-carotene and ascorbic acid. In terms of triglycerides and glucose AUC, the green leafy vegetables meal showed a better recovery to the baseline value after four hours than the standard meal. Three weeks' supplementation of green leafy vegetables with more oil resulted in significant increase of plasma beta-carotene (51%) and hemoglobin (9%). Green leafy vegetables with vitamin E showed a significant increase in plasma beta-carotene (40%), hemoglobin (8%), and plasma vitamin C (6%). Supplementing beta-carotene without green leafy vegetables significantly increased hemoglobin (11%) and plasma zinc (14%) in addition to beta-carotene. Multiple regression analyses weighted for energy intake indicated a significant association of percent increase in hemoglobin with intakes of iron, riboflavin, folic acid, beta-carotene, copper, phytate, and fiber (p<0.01), percent change in plasma zinc with intakes of zinc, beta-carotene, vitamin C, riboflavin, copper, iron, and thiamin (p<0.01), percent change in vitamin C with intakes of vitamin C, vitamin E, niacin, riboflavin, thiamin, beta-carotene, zinc, phytate, and fiber (p<0.05), and percent change in plasma beta-carotene with intakes of beta-carotene, thiamin, folic acid, zinc, phytate, and tannins (p<0.05).

  1. Guedon, C., Ducrotte, P., Antoine, J. M., Denis, P., Colin, R., and Lerebours, E. Does chronic supplementation of the diet with dietary fibre extracted from pea or carrot affect colonic motility in man? Br J Nutr 1996;76(1):51-61. 8774216
  2. Cummings, J. H., Branch, W., Jenkins, D. J., Southgate, D. A., Houston, H., and James, W. P. Colonic response to dietary fibre from carrot, cabbage, apple, bran. Lancet 1-7-1978;1(8054):5-9. 74533
  3. Agte, V., Jahagirdar, M., and Chiplonkar, S. GLV supplements increased plasma beta-carotene, vitamin C, zinc and hemoglobin in young healthy adults. Eur J Nutr 2006;45(1):29-36. 15834756
  4. Gustafsson, K., Asp, N. G., Hagander, B., and Nyman, M. Dose-response effects of boiled carrots and effects of carrots in lactic acid in mixed meals on glycaemic response and satiety. Eur J Clin Nutr 1994;48(6):386-396. 7925220
  5. Kamboj, V. P. and Dhawan, B. N. Research on plants for fertility regulation in India. J Ethnopharmacol 1982;6(2):191-226. 6752588
  6. Wisker, E., Schweizer, T. F., Daniel, M., and Feldheim, W. Fibre-mediated physiological effects of raw and processed carrots in humans. Br J Nutr 1994;72(4):579-599. 7986789
  7. Pietschnig, B., Javaid, N., Haschke, F., Huemer, C., and Schuster, E. [Acute diarrheal diseases. Treatment with carrot-rice viscous solution is more effective than ORS solution]. Monatsschr Kinderheilkd 1992;140(7):426-430. 1501619
  8. Kaplan, R. Carrot addiction. Aust N Z J Psychiatry 1996;30(5):698-700. 8902181
  9. Briviba, K., Schnabele, K., Rechkemmer, G., and Bub, A. Supplementation of a diet low in carotenoids with tomato or carrot juice does not affect lipid peroxidation in plasma and feces of healthy men. J Nutr 2004;134(5):1081-1083. 15113949
  10. Bub, A., Barth, S. W., Watzl, B., Briviba, K., and Rechkemmer, G. Paraoxonase 1 Q192R (PON1-192) polymorphism is associated with reduced lipid peroxidation in healthy young men on a low-carotenoid diet supplemented with tomato juice. Br J Nutr 2005;93(3):291-297. 15877867
  11. Bub, A., Watzl, B., Abrahamse, L., Delincee, H., Adam, S., Wever, J., Muller, H., and Rechkemmer, G. Moderate intervention with carotenoid-rich vegetable products reduces lipid peroxidation in men. J Nutr 2000;130(9):2200-2206. 10958813
  12. Pool-Zobel, B. L., Bub, A., Muller, H., Wollowski, I., and Rechkemmer, G. Consumption of vegetables reduces genetic damage in humans: first results of a human intervention trial with carotenoid-rich foods. Carcinogenesis 1997;18(9):1847-1850. 9328185
  13. Young, J. F., Dragsted, L. O., Daneshvar, B., Lauridsen, S. T., Hansen, M., and Sandstrom, B. The effect of grape-skin extract on oxidative status. Br J Nutr 2000;84(4):505-513. 11103221
  14. el Arab, A. E., Khalil, F., and Hussein, L. Vitamin A deficiency among preschool children in a rural area of Egypt: the results of dietary assessment and biochemical assay. Int J Food Sci Nutr 2002;53(6):465-474. 12590741
  15. Horvitz, M. A., Simon, P. W., and Tanumihardjo, S. A. Lycopene and beta-carotene are bioavailable from lycopene 'red' carrots in humans. Eur J Clin Nutr 2004;58(5):803-811. 15116084
  16. Moller, P. and Loft, S. Oxidative DNA damage in human white blood cells in dietary antioxidant intervention studies. Am J Clin Nutr 2002;76(2):303-310. 12144999
  17. Watzl, B., Bub, A., Briviba, K., and Rechkemmer, G. Supplementation of a low-carotenoid diet with tomato or carrot juice modulates immune functions in healthy men. Ann Nutr Metab 2003;47(6):255-261. 14520020
  18. Watzl, B., Bub, A., Brandstetter, B. R., and Rechkemmer, G. Modulation of human T-lymphocyte functions by the consumption of carotenoid-rich vegetables. Br J Nutr 1999;82(5):383-389. 10673911
  19. Kurilich, A. C., Clevidence, B. A., Britz, S. J., Simon, P. W., and Novotny, J. A. Plasma and urine responses are lower for acylated vs nonacylated anthocyanins from raw and cooked purple carrots. J Agric Food Chem 8-10-2005;53(16):6537-6542. 16076146
  20. Thurmann, P. A., Steffen, J., Zwernemann, C., Aebischer, C. P., Cohn, W., Wendt, G., and Schalch, W. Plasma concentration response to drinks containing beta-carotene as carrot juice or formulated as a water dispersible powder. Eur J Nutr 2002;41(5):228-235. 12395217
  21. Cardinault, N., Tyssandier, V., Grolier, P., Winklhofer-Roob, B. M., Ribalta, J., Bouteloup-Demange, C., Rock, E., and Borel, P. Comparison of the postprandial chylomicron carotenoid responses in young and older subjects. Eur J Nutr 2003;42(6):315-323. 14673604
  22. Tyssandier, V., Reboul, E., Dumas, J. F., Bouteloup-Demange, C., Armand, M., Marcand, J., Sallas, M., and Borel, P. Processing of vegetable-borne carotenoids in the human stomach and duodenum. Am J Physiol Gastrointest Liver Physiol 2003;284(6):G913-G923. 12736146
  23. Kirkman, L. M., Lampe, J. W., Campbell, D. R., Martini, M. C., and Slavin, J. L. Urinary lignan and isoflavonoid excretion in men and women consuming vegetable and soy diets. Nutr Cancer 1995;24(1):1-12. 7491293

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