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: