Carrots are perhaps best known for their rich supply of the antioxidant nutrient that was actually named for them: beta-carotene. However, these delicious root vegetables are the source not only of beta-carotene, but also of a wide variety of antioxidants and other health-supporting nutrients. The areas of antioxidant benefits, cardiovascular benefits, and anti-cancer benefits are the best-researched areas of health research with respect to dietary intake of carrots.
Antioxidant Benefits
All varieties of carrots contain valuable amounts of antioxidant nutrients. Included here are traditional antioxidants like vitamin C, as well as phytonutrient antioxidants like beta-carotene. The list of carrot phytonutrient antioxidants is by no means limited to beta-carotene, however. This list includes:
Carotenoids
alpha-carotene
beta-carotene
lutein
Hydroxycinnamic acids
caffeic acid
coumaric acid
ferulic acid
Anthocyanindins
cyanidins
malvidins
Different varieties of carrots contain differing amounts of these antioxidant phytonutrients. Red and purple carrots, for example, are best known for the rich anthocyanin content. Oranges are particularly outstanding in terms of beta-carotene, which accounts for 65% of their total carotenoid content. In yellow carrots, 50% of the total carotenoids come from lutein. You're going to receive outstanding antioxidant benefits from each of these carrot varieties!
Cardiovascular Benefits
Given their antioxidant richness, it's not surprising to find numerous research studies documenting the cardiovascular benefits of carrots. Our cardiovascular system needs constant protection from antioxidant damage. This is particularly true of our arteries, which are responsible for carrying highly oxygenated blood.
A recent study from the Netherlands, in which participants were followed for a period of 10 years, has given us some fascinating new information about carrots and our risk of cardiovascular disease (CVD). In this study, intake of fruits and vegetables was categorized by color. The researchers focused on four color categories: green, orange/yellow, red/purple, and white. Out of these four categories, orange/yellow (and in particular, foods with deeper shades of orange and yellow) was determined to be the most protective against CVD. Within this dark orange/yellow food group, carrots were determined to be the single most risk-reducing food. Participants who had the least carrot intake had the least amount of CVD risk reduction, even though they still received risk-reducing benefits from their carrot intake. However, participants who ate at least 25 more grams of carrots (with 25 grams being less than one-quarter of a cup) had a significantly lower risk of CVD. And the groups of participants who ate 50- or 75-grams more had an even more greatly reduced risk of CVD! We're not sure how any study could better demonstrate how easy it can be to lower CVD risk by making a food like carrot part of the everyday diet.
Antioxidant nutrients in carrots are believed to explain many of the cardioprotective benefits provided by these root vegetables. The many different kinds of carrot antioxidants are most likely to work together and provide us with cardiovascular benefits that we could not obtain from any of these antioxidants alone if they were split apart and consumed individually, in isolation from each other. The synergistic effect of carrot antioxidants is a great example of a whole food and its uniqueness as a source of nourishment.
Yet in addition to the diverse mixture of carrot antioxidants, there is yet another category of carrot phytonutrient that is believed to help explain carrot protection against cardiovascular disease.That category is polyacetylenes. Polyacetylenes are unique phytonutrients made from metabolism of particular fatty acids (often involving crepenynic acid, stearolic acid and tariric acid). They are particularly common in the Apiaceae/Umbelliferae family of plants (which includes carrot). The two best-researched polyacetylenes in carrot are falcarinol and falcarindiol. Preliminary research on animals and in the lab has shown that carrot polyacetylenes have anti-inflammatory properties and anti-aggregatory properties (that help prevent excessive clumping together of red blood cells). So in addition to the unique mix of antioxidants in carrot, polyacetylenes may play a key role in the cardiovascular protection provided by this amazing food.
Vision Health
While you might expect to find a large number of human research studies documenting the benefits of carrot intake for eye health, there are relatively few studies in this area. Most studies about carotenoids and eye health have focused on carotenoid levels in the bloodstream and the activities of the carotenoids themselves, rather than the food origins of carotenoids (like carrots). Still, we have found some smaller scale human studies that show clear benefits of carrot intake for eye health. For example, researchers at the Jules Stein Institute at the University of California at Los Angeles determined that women who consume carrots at least twice per week - in comparison to women who consume carrots less than once per week - have significantly lower rates of glaucoma (damage to the optic nerve often associated with excessive pressure inside the eye). Intake of geranyl acetate - one of the photonutrients that is present in carrot seeds (and sometimes extracted from purified carrot seed oil) has also been repeatedly associated with reduced risk of cataracts in animal studies. However, researchers have yet to analyze the amount of geranyl acetate in the root portion of the carrot and the impact of dietary intake on risk of cataracts.
Anti-Cancer Benefits
The anti-cancer benefits of carrot have been best researched in the area of colon cancer. Some of this research has involved actual intake of carrot juice by human participants, and other research has involved the study of human cancer cells types in the lab. While much more research is needed in this area, the study results to date have been encouraging. Lab studies have shown the ability of carrot extracts to inhibit the grown of colon cancer cells, and the polyacetylenes found in carrot (especially falcarinol) have been specifically linked to this inhibitory effect. In studies of carrot juice intake, small but significant effects on colon cell health have been shown for participants who consumed about 1.5 cups of fresh carrot juice per day.
We're confident that future studies in this area will show carrot intake as being protective against risk of colon cancer. Carrots are simply too rich in digestive tract-supporting fiber, antioxidant nutrients, and unique phytonutrients like falcarinol to be neutral when it comes to support of the lower digestive tract and colon cancer protection.
Description
As one of the most popular root vegetables in the U.S. - and widely enjoyed in many other countries as well - carrots almost feel like an old friend for many people who are looking for just the right crunchy snack or addition to a salad. We've even seen one study of 8-11 year-old children in France who were given pictures of 54 vegetables and were mostly likely to pick out carrots (along with lettuce and tomatoes) as easily identifiable and likeable vegetables. In the U.S., there seems to be an equal liking for carrots at the other end of the age spectrum as well. Individuals 76 years of age and older eat twice as many carrots as individuals under 40, with the overall average being about 1 cup of carrots per week.
It's easiest to identify carrots as belonging to the Umbelliferae family of plants, since their leafy greens form an umbrella-like cluster at the top of the root. However, this same family of plants is also commonly known as the Apiaceae family. While the International Code of Botanical Nomenclature accepts both designations, the use of Apiaceae is becoming more and more common in carrot research. This same botanical family includes parsley, anise, celery, parsnips, fennel, caraway, cumin and dill.
The name "carrot" comes from the Greek word "karoton," whose first three letters (kar) are used to designate anything with a horn-like shape. (That horn-like shape, of course, refers to the taproot of the carrot that is the plant part we're most accustomed to consuming in the U.S.). The beta-carotene that is found in carrots was actually named for the carrot itself!
Even though U.S. consumers are most familiar with carrots as root vegetables bright orange in color, an amazing variety of colors are found worldwide for this vegetable. (All of these color varieties, however, still belong to the same genus and species of plant, Daucus carota.) Here is a short list of some of the more popular carrot varieties, categorized by color:
History
The carrot can trace its ancestry back thousands of years, originally having been cultivated in central Asian and Middle Eastern countries, along with parts of Europe. These original carrots looked different from those that we are accustomed to today, featuring red, purple, and yellow coloring rather than the bright orange that we've become accustomed to in U.S. supermarkets. Carrots became widely cultivated in Europe during the 15th and 16th centuries and were first brought over to North America during this same general time period.
In today's commercial marketplace, China currently produces about one-third of all carrots bought and sold worldwide. Russia is the second largest carrot producer, with the U.S. following a close third. Many European countries produce substantial amounts of carrots (over 400,000 metric tons) and Turkey, Mexico, India, Indonesia, Australia and Canada are also important countries in the worldwide production of carrots. Within the U.S., about 12,000 acres of carrots for processing are planted each year, resulting in about 320,000 tons of carrots. Over 80% of all fresh market carrot production in the U.S. comes from California, with Michigan and Texas emerging as the next two largest fresh production states.
Currently,U.S. adults average about 12 pounds of carrot intake each year. Approximately 9 pounds are being consumed in fresh form, with the other 3 pounds are being consumed in frozen or canned products. This amount translates into approximately 1 cup of carrots each week in fresh, frozen, or canned form.
How to Select and Store
Carrot roots should be firm, smooth, relatively straight and bright in color. The deeper the orange-color, the more beta-carotene is present in the carrot. Avoid carrots that are excessively cracked or forked as well as those that are limp or rubbery. In addition, if the carrots do not have their tops attached, look at the stem end and ensure that it is not darkly colored as this is also a sign of age. If the green tops are attached, they should be brightly colored, feathery and not wilted. Since the sugars are concentrated in the carrots' core, generally those with larger diameters will have a larger core and therefore be sweeter.
Carrots are hardy vegetables that will keep longer than many others if stored properly. The trick to preserving the freshness of carrot roots is to minimize the amount of moisture they lose. To do this, make sure to store them in the coolest part of the refrigerator in a plastic bag or wrapped in a paper towel, which will reduce the amount of condensation that is able to form. They should be able to keep fresh for about two weeks. Research has shown that the especially valuable (all-E)-beta-carotene isomer is well-retained in carrots if stored properly. Carrots should also be stored away from apples, pears, potatoes and other fruits and vegetables that produce ethylene gas since it will cause them to become bitter.
If you purchase carrot roots with attached green tops, the tops should be cut off before storing in the refrigerator since they will cause the carrots to wilt prematurely as they pull moisture from the roots. While the tops can be stored in the refrigerator, kept moist by being wrapped in a damp paper, they should really be used soon after purchase since they are fragile and will quickly begin to wilt.
Wash carrot roots and gently scrub them with a vegetable brush right before eating. Unless the carrots are old, thick or not grown organically, it is not necessary to peel them. If they are not organically grown, peel them; most all conventionally grown carrots are grown using pesticides and other chemicals. If the stem end is green, it should be cut away as it will be bitter. Depending upon the recipe or your personal preference, carrots can be left whole or julienned, grated, shredded or sliced into sticks or rounds.
Carrots are delicious eaten raw or cooked. While heating can often damage some of the delicate phytonutrients in vegetables, the beta-carotene as found in carrots has been shown to be surprisingly heat-stable. In fact, carrots' beta-carotene may become more bioavailable through well-timed steaming. Still, be careful not to overcook carrots if you want to your carrots to retain their maximum flavor and strong overall nutritional value.
The Healthiest Way of Cooking Carrots
Of all of the cooking methods we tried when cooking carrots, our favorite is Healthy Steaming. We think that it provides the greatest flavor and is also a method that allows for concentrated nutrient retention. In fact, participants in a recent research study agreed with us. When study participants were asked to evaluate the flavor and overall acceptability of different carrot cooking methods, they significantly favored the flavor and overall acceptability of steamed carrots to boiled carrots. This preference was even expressed by participants who had always boiled carrots in their previous kitchen practices!
To Healthy Steamed carrots, fill the bottom of the steamer with 2 inches of water and bring to a rapid boil. Slice carrots ¼-inch thick and steam for 5 minutes. Transfer to a bowl. For more flavor, toss carrots with our Mediterranean Dressing. (Looking for carrots with extra zing? Try our Carrots with Honey Mustard Sauce recipe.)
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