Food as Medicine Update: Carrot

HerbalEGram: Volume 15, Issue 4, April 2018 (Daucus carota subsp. sativus, Apiaceae) Editor’s Note: As the Food as Medicine project has evolved at the American Botanical Council (ABC), the editors of HerbalEGram will revisit older articles in this series and update them with current research. This effort will hopefully improve the accuracy and relevance of these articles, in keeping with our commitment to education and empowerment. Food as Medicine: Carrot was originally published in the December 2014 issue of HerbalEGram. The basic materials for this series were compiled by dietetic interns from Texas State University in San Marcos and the University of Texas at Austin through ABC’s Dietetic Internship Program, led by ABC Education Coordinator Jenny Perez. We would like to acknowledge Perez, ABC Special Projects Director Gayle Engels, and ABC Chief Science Officer Stefan Gafner, PhD, for their contributions to this project. By Hannah Baumana and Kathryn MacLeanb a HerbalGram Assistant Editor b ABC Dietetics Intern (Texas State, 2012) Overview Widely available at most supermarkets, the common root vegetable carrot (Daucus carota subsp. sativus, Apiaceae) is a biennial plant with erect, green stems and fine, feathery leaves.1 The plant produces densely clustered white blossoms in an umbrella shape, which is typical of plants in the Apiaceae family. The edible taproot comes in a variety of colors: orange is the most widely available in stores, but the root can also be white, yellow, red, or purple.2 The modern carrot is a domesticated cultivar of wild carrot, Daucus carota, also known by the common name Queen Anne’s lace. Indigenous to Europe and southwestern Asia, frost-tolerant carrots are now cultivated in a wide range of environments.1 Carrots are popular with home gardeners due to their colorful varieties as well as their hardiness. Phytochemicals and Constituents Favored for their sweet flavor and versatility, carrots contain a vast array of vitamins and minerals. Carrots contain the flavonoid quercetin, as well as carotenoids such as alpha- and beta-carotene and lycopene.1 Beta-carotene, which is converted by the body into vitamin A, is a powerful antioxidant that protects the body from free radicals and helps maintain healthy skin and eyes.3 These compounds also have shown anti-mutagenic activity in vitro, and may play a role in decreasing the risk of some cancers. The different colors of carrots reveal the various concentrations of phytochemicals.4 Carotenoids give yellow, orange, and red carrots their colors, while anthocyanins produce the deep purple variety. Orange carrots contain high quantities of beta-carotene. Yellow carrots contain low quantities of beta-carotene, but higher levels of lutein, which may help maintain healthy eyesight and protect from age-related macular degeneration. Red carrots contain lycopene, a potent antioxidant with potential anticancer activity, in similar concentrations to that of tomato (Solanum lycopersicum, Solanaceae). Red carrots also contain moderate levels of alpha- and beta-carotene and lutein. Purple carrots contain high levels of anthocyanins, antioxidants which have shown anti-inflammatory and cardio-protective benefits. The white variety has low levels of anthocyanins, but contains high levels of potassium. Historical and Commercial Uses Purple carrot was the most common color cultivar until about 450 years ago. A popular but discredited theory claims that the orange variety was exclusively cultivated in Holland as a sign of Dutch nationalism to honor William of Orange, leader of the Dutch rebellion in 1568. The exact reason why the orange cultivar became the dominant variety is unknown, though genetic evidence shows that orange carrots developed from a yellow cultivar.5 Cultivation of carrot likely spread west from Persia through the Mediterranean and then east to China, India, and Japan.1 The ancient Greeks used carrot as both food and medicine: Dioscorides, a Greek physician from the first century, recommended carrot seed as an emmenagogue (to stimulate or increase menstrual flow) and for the treatment of frequent, painful urination.6 The root was considered an aphrodisiac, and a topical application of the leaves mixed with honey was recommended for the treatment of ulcers.7 He also included a recipe for a carrot drink in his treatise De Materia Medica. In the 10th century, the Old English Herbarium and Bald’s Leechbook indicated the use of the root as an emmenagogue as well as a treatment for smallpox and cough.8 Both root and seed have recorded uses to promote menstruation or as a diuretic. A different species, the wild American carrot (D. pusillus), has an ethnomedicinal history of use among many Native American tribes as a remedy for cold, fever, itching, and snake bites.9 Modern Research In vitro research suggests that carrot root may have cytotoxic properties,10-12 and clinical evidence suggests that carrot consumption may be beneficial for people with high blood pressure13 and cardiovascular disease.14 Carrot root consumption may be beneficial for nursing mothers. A randomized trial suggested that babies of women who drank carrot juice while nursing more easily accepted carrot as a solid food, in contrast to broccoli (Brassica oleracea, Brassicaceae) to which they were previously unexposed.15 The outcome of this study is not limited to carrot, and suggests that nursing mothers can begin exposing children to healthy eating habits through their own intake of vegetables. In an open-label, non-controlled trial, researchers found that mothers who supplemented their diet with carrot paste saw significantly increased levels of beta-carotene in breastmilk over baseline, which can also improve an infant’s overall health and development.16 Carrot seed extract and essential oil have shown antibacterial, antifungal, and antiviral properties in vitro.17 Animal studies have also explored the possible hepatoprotective, anti-inflammatory, cholesterol-lowering, wound-healing, and cognition-enhancing benefits of carrot seed extract and essential oil.1 Consumer Considerations Consuming large amounts of beta-carotene, especially from carrots, can result in a harmless side effect called carotenemia, which temporarily yellows the skin.3 Infants, whose commercial foods often contain carrot puree as an added ingredient, are most likely to get carotenemia. The yellowing effect subsides as the body processes the excess beta-carotene. Carrots can be enjoyed raw or cooked, as they retain their nutrients during the cooking process.18 Nutrient Profile19 Macronutrient Profile: (per 1 cup chopped raw carrot [approx. 128 grams]) 52 calories 1.19 g protein 12.26 g carbohydrate 0.31 g fat Secondary Metabolites: (per 1 cup chopped raw carrot [approx. 128 grams]) Excellent source of: Vitamin A: 21,384 IU mcg (356.4% DV) Very good source of: Vitamin K: 16.9 mcg (16.1% DV) Molybdenum: 6.1 mcg (13.6% DV) Vitamin B6: 0.17 mg (13.1% DV) Dietary Fiber: 3.6 g (12.9% DV) Good source of: Vitamin C: 7.6 mg (9.2% DV) Manganese: 0.18 mg (8.8% DV) Niacin: 1.3 mg (8.7% DV) Potassium: 410 mg (8.7% DV) Thiamin: 0.08 mg (7.3% DV) Phosphorus: 45 mg (6.4% DV) Folate: 24 mcg (6% DV) Also provides: Magnesium: 15 mg (4.2% DV) DV = Daily Value as established by the US Food and Drug Administration, based on a 2,000-calorie diet. Recipe: Spicy Pickled Carrots Adapted from Alton Brown20 Ingredients: 1 pound baby carrots 2 cloves garlic, peeled and crushed 1 cup water 1/2 cup sugar 1 1/2 cups apple cider vinegar 1/2 teaspoon yellow mustard seeds 1 1/2 teaspoons kosher salt 1 teaspoon dried chili flakes 2 dried red chilies Directions: Place carrots and garlic in a 1-quart, spring-top glass jar. In a non-reactive sauce pan, bring the water, sugar, cider vinegar, mustard seeds, salt, and dried chili flakes to a boil, stirring to dissolve the sugar and salt. Boil for 4 minutes. Slowly pour the pickling liquid into the jar, covering the carrots and garlic completely. Submerge the chilies in the jar and cool before sealing. Refrigerate for two days (for a milder pickle) or a week (for a spicier pickle). These will get hotter the longer they are kept. All images ©2018 Steven Foster References Mahammad SB, Saliyan T, Satish S, Hedge K. Therapeutic uses of Daucus carota: A review. 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Portland, OR: Timber Press; 1998. Bhanot A, Sharma R, Noolvi M. Natural sources as potential anti-cancer agents: A review. International Journal of Phytomedicine. April 2011;3(1):9-26. Aggarwal B, Shishodia S. Molecular targets of dietary agents for prevention and therapy of cancer. Biochemical Pharmacology. May 14, 2006:1397, 1421. Rana Z, Malcolm R. C, Christine L. Le M. Bioactive chemicals from carrot (Daucus carota) juice extracts for the treatment of leukemia. Journal of Medicinal Food. November 2011;14(11):1303-1312. Potter AS, Foroudi S, Stamatikos A, Patil BS, Deyhim F. Drinking carrot juice increases total antioxidant status and decreases lipid peroxidation in adults. Nutr J. 2011;10:96. Buijsse B, Feskens E, Kwape L, Kok F, Kromhout D. Both α- and β-carotene, but not tocopherols and vitamin c, are inversely related to 15-year cardiovascular mortality in Dutch elderly men. Journal of Nutrition. 2008;138(2):344-350. Mennella JA, Daniels LM, Reiter AR. Learning to like vegetables during breastfeeding: A randomized clinical trial of lactating mothers and infants. Am J Clin Nutr. 2017;106(1):67-76. Haftel L, Berkovich Z, Reifen R. Elevated milk β-carotene and lycopene after carrot and tomato paste supplementation. Nutrition. 2015;31(3):443-445. Brochot A, Guilbot A, Haddioui L, Roques C. Antibacterial, antifungal, and antiviral effects of three essential oil blends. Microbiologyopen. 2017 Aug;6(4). Rock CL, Lovalvo JL, Emenhiser C, Ruffin MT, Flatt SW, Schwartz SJ. Bioavailability of beta-carotene is lower in raw than in processed carrots and spinach in women. J Nutr. 1998;128:913-916. Basic Report: 11124, Carrots, raw. National Nutrient Database for Standard Reference Release 28. May 2016. United States Department of Agriculture website. Available here. Accessed March 23, 2018. Brown A. Firecrackers. Food Network website. Available here. Accessed March 23, 2018.