Carrot Nutrition

From those 3 elements, carrots benefit our bodies by:

	Boosting immunity (especially among older people).
	Reducing photosensitivity (beta-carotene protects the skin from sun damage).
	Improving symptoms of HIV.
	Easing alcohol withdrawal symptoms.
	Helping to heal minor wounds and injuries. Prevent infection: Raw carrot or boiled are applied on cuts and wounds as an antiseptic.
	Reducing the risk of heart disease.
	Reducing the risk of high blood pressure.
	Cleansing the liver, and when consumed regularly, can help the liver excrete fats and bile.
	Fighting bronchitis.
	Fighting infection (vitamin A keeps cell membranes healthy, making them stronger against disease-causing micro organisms)
	Improving muscle, flesh, and skin health.
	Helping fight aneamia.
	Reducing acne.
	Improving eye health
	Anti ageing -Carrots are considered anti-ageing foods as they are rich in beta-carotene, an antioxidant that fights free radicals.
	Boost beauty: Carrots are rich in antioxidants and vitamin A, both responsible for healthy skin, hair and nails
	Dental health: Consumption of carrots improves the dental health by clearing plaque. Biting on carrots increases the production of saliva, hence balances the acid level which fight cavity-causing bacteria.

Pigment Power in Carrot Colour

Have you ever seen a purple carrot? How about white, yellow, red or black? Most people haven't, even though such carrots have existed for hundreds of years. They are available in good health food stores, often called "Rainbow Packs".

Carrots were originally purple or red, with a thin root. Orange carrots arrived from natural mutations of yellow forms, and then by human selection and development, probably in the Netherlands. It is thought that humans made selections from a genepool involving yellow rooted eastern carrots, cultivated white-rooted derivatives of wild carrot (grown as medicinal plants since classical times) and wild unselected populations of adjacent Daucus Carota subspecies in Europe and the Mediterranean.  It is thought that Dutch breeders used a mutant seed from North Africa to develop the orange variety into a stable and reliable plant for domestication. (see the colour timeline here)

The first carrots were grown for medicinal purposes, perhaps the medicine tasted good! There is lots more in the history pages - here.

Research at the University of Wisconsin-Madison suggests that pigments in these colourful carrots, which taste just like regular carrots, may help prevent heart disease and cancer, and reduce cholesterol. Studies examining the health benefits of fruits and vegetables are revealing the disease-preventive powers of the pigments that give plants their distinctive colours.

Orange carrots get their colour from beta carotene, a pigment the body converts to vitamin A. Vitamin A deficiency, although rare in the United States, poses a major public health problem in developing countries second only to protein malnutrition.

According to the World Health Organization, vitamin A deficiency partially or totally blinds nearly 350,000 children from more than 75 countries every year. Roughly 60 percent of these children die within months of going blind. However, vitamin A deficiency is preventable.

Factors Affecting the Colour of Carrots

The main variation in the colour of carrot is due to genotype, the development of the plant, the temperature during the growing season and also other agronomic practices such as the use of fertilisers. (reference Bajaj et al 1980, Van de Burg et 2000 - Plant food Human Nutrition 30: 97-107; Journal of Food Science and Agric 80:880-912)

Carrot (Daucus carota) is a biennial plant that accumulates massive amounts of carotenoid pigments in the storage root. Although the root of carrot plants was white before domestication, intensive breeding generated the currently known carotenoid-rich varieties, including the widely popular orange carrots that accumulate very high levels of the pro-vitamin A carotenoids b-carotene and, to a lower extent, a-carotene. Recent studies have shown that the developmental program responsible for the accumulation of these health-promoting carotenes in underground roots can be completely altered when roots are exposed to light. Illuminated root sections do not enlarge as much as dark-grown roots, and they contain chloroplasts with high levels of lutein instead of the b-carotene-rich chromoplasts found in underground roots. Analysis of carotenoid gene expression in roots either exposed or not to light has contributed to better understand the contribution of developmental and environmental cues to the root carotenoid profile.

Young carrot roots are pale but after the first month of growth they start accumulating carotenoids to reach highest levels in about 3 months, just before secondary growth is completed. It is likely that wild carrot plants had uncolored roots of a bitter taste and a woody core but were initially cultivated because of their aromatic leaves and seeds. Carrot domestication probably took place around the 10th century but despite intensive breeding procedures since the 19th century, the background structure coming from demographic and early cultivation history still persists in currently cultivated carrot germplasm. At present, carrots (i.e. mature D. carota roots) are available in a range of colors, although orange varieties are most popular. Even though the high carotene content in carrots makes them one of the richest pro-vitamin A sources in the human diet, the mechanisms regulating their production remained poorly known until recently. (ref -  Biosynthesis of carotenoids in carrot: An underground story comes to light Manuel Rodriguez-Concepcion,, Claudia Stange - Archives of Biochemistry and Biophysics 539 (2013) 110–116)

Main factors affecting colour include:

1. Temperatures above and below the optimum (above 70° and below 60°F) reduce the colour of carrots.

2. Spring and summer carrots are often of better colour than autumn and winter.

3. Carrots grown on sandy soils and soils high in organic matter produce a higher colour than did carrots on silt loams.

4. Excessive water decreases the colour.

5. Reducing the number of daylight hours has reduced the colour.

Colour is more intense in the older portions of the root. It decreases from the epidermis and centre toward the cambium, and from the top to the bottom.

Studies have been carried out in the USA on the differing properties of different coloured carrots with the following results:

Orange Carrots contain beta carotene, with some alpha-carotene, both of which are orange pigments. High in Vitamin A essential for well-being, healthy eyes. These carrots originate from Europe and the Middle East. Like all carrots these are a good source of fibre, which is vital for healthy gastrointestinal tracts and is linked to reducing cholesterol. Their pre-dominant pigment is beta-carotene; the orange pigment which is converted by the liver to vitamin A which is important for healthy vision. It forms rhodopsin, which the eye needs to see in dim light. This is accomplished by raising the effectiveness of the light sensitive area of the retina. Vitamin A also maintains the surface linings of the respiratory, urinary, and intestinal tracts, and regulates the immune system by helping white blood cells fight infections.
Yellow carrots contain xanthophylls and lutein, pigments similar to beta carotene, which help develop healthy eyes aid in the fight against macular degeneration and may prevent lung and other cancers and reduce the risk of astherosclerosis (hardening of the arteries). These came from the Middle East. The major pigment found in the yellow carrots is xanthophyll which helps develop healthy eyes. Studies have shown that intake of xanthophyll-rich foods are associated with a significant reduction in the risk for cataract (up to 20%) and for age-related macular degeneration (up to 40%) (Moeller, Jacques & Blumberg 2000). Yellow Carrot page.
Red carrots are tinted by lycopene, (another form of carotene) a pigment also found in tomatoes and watermelon; lycopene is associated with the reduced risk of macular degeneration, serum lipid oxidation, helps prevent heart disease and a wide variety of cancers including prostate cancer. Originally from India and China. Red carrots contain the pigment known as lycopene which has been associated with a lowered risk of prostate cancer in men and heart disease. It also helps maintain healthy skin. Red Carrot page
White carrots lack any pigmentation, but do contain other health-promoting substances called phytochemicals, natural bioactive compounds found in plant foods that work with nutrients and dietary fibre to protect against disease. One might say these are the least healthy of carrots. They originate from Afghanistan, Iran, Pakistan. These chemicals may be important in reducing the risk of atherosclerosis , which is the build up of fatty deposits in artery walls. White carrots are preferably used in baby foods to prevent them from forming orange skin. White carrot page
Purple carrots (usually orange inside) have even more beta carotene than their orange cousins, and get their pigment from an entirely different class, the anthocyanins, these pigments act as powerful antioxidants that protect key cell components, grabbing and holding on to harmful free radicals in the body. Anthocyanins also help prevent heart disease by slowing blood clotting and are good anti inflammatory agents. These originate from Turkey, and the Middle and Far East. Purple carrot page
The Purple Haze variety have a more purple/red and white centre. Purple carrots neutralize the damaging effects of free radicals which disrupt the structure of other molecules leading to cellular damage, aging, and various health problems. Anti-inflammatory properties of anthocyanins have also been observed. They neutralize enzymes that destroy connective tissue and they repair damaged proteins in blood vessel walls. Finally, anthocyanins may prevent heart disease by slowing blood clotting and inhibiting the absorption of LDL, “the bad cholesterol.”
Black Carrots contain anthocyanins, part of the flavonoid family with antioxidant properties. Flavonoids are currently under investigation as anticancer compounds, as free radical scavengers in living systems, as well as inhibitors of LDL (the bad) cholesterol and the black carrot anthocyanins are especially active. The Black variety has anti-bacterial and anti-fungicidal properties and oil made from its seed can help control scalp itchiness and provides essential nutrients for hair growth. The ancient black carrot has been making a comeback, not so much for culinary purposes but as a source of natural food colorants. These originate from Turkey, and the Middle and Far East. Black carrot page

See more colour variations here (new window) - University of Agriculture, Krakow.

Factors affecting taste/flavour

The taste of carrots is a unique composition between sweet, fruity and more harsh or bitter flavours. Many factors affect the balance between the different flavours in carrots and thus contribute to the final taste. Sweet taste is more common in the centre and lower, tip, part of the carrot. The phloem is mostly sweeter and also bitterer than the xylem. Bitter taste is more often detected in the upper and outer part of the carrot. The amount of sugar in the carrots has a clear correlation to the perception of sweetness. The amount of sugar can also contribute in masking bitter taste in carrots. One possible reason for the increases in bitter taste during storage is decreasing sugar content. The sugar in carrots consists mainly of sucrose, glucose and fructose. During the seedling phase no soluble sugar is stored, in the second phase only reducing sugar and in the third phase, starting some 50 days after sowing mainly sucrose is stored in the carrot root. The reduction in sugar during storage mainly concerns sucrose. The total amount of sugars do not differ so much between different parts of the carrot.(ref - Introductory Paper at the Faculty of Landscape Planning, Horticulture and Agricultural Science 2007:2 Swedish University of Agricultural Sciences Alnarp, September 2007)

Carrot flavour and aroma are made up of sugars and terpenoids. The natural sugars—sucrose, glucose, fructose, and maltose give carrots their sweet flavour. The organic chemicals or compounds called terpenoids give carrots their characteristic aroma.

The flavor of raw carrots is mainly due to sugars and volatile terpenoids, with the latter accounting for most odour. There certainly are other chemicals involved but these are the major players. Texture also plays a very large role in perception of carrot flavor, and that's primarily due to structural carbohydrates, primarily pectin compounds, but not much is known about them, other than that they very widely across carrot cultivars

Young carrots develop terpenoids first; these are volatile compounds, meaning they are aromatic. Terpenoids can smell like pine, wood, citrus, and turpentine. A carrot harvested too early can taste bitter and soapy.

As carrots grow, natural sugars develop through photosynthesis and are stored in the root. When days are warm and nights cool, carrots make sugar during the day, but don’t expend that sugar energy at night. In other words, the carrot grows sweeter. (When nights are warm–60°F or greater, carrots respire and burn but sugar energy.)

Carrots are sweetest when they mature at the time of year when the days are warm and the nights are cool. As well, the best time to harvest a carrot is at the end of a warm day as it finishes manufacturing new sugars through photosynthesis.

In the life of a carrot, terpenoids-driven taste come first and, in time, are balanced with sugar flavors. The sweet carroty flavor is the perfect combination of terpenoids and sugars.

Cooking breaks down the terpenoids in carrots and at the same time releases natural sugars. Cooked carrots will be sweeter than raw carrots. More on taste here (pdf)

Some Sweet Tasting Carrot Varieties:

Nairobi: An early Nantes type bred for vigorous quick growth, good colour and flavour. Smooth cylindrical roots with little core. Early and maincrop. 8 inches long. The commercial growers favourite (UK)

Bolero: sweet, juicy, crunchy, orange to 7 inches long; 75 days to harvest; hybrid.

Ithaca: sweet, light taste, deep orange to 7 inches long; 65 days to harvest; hybrid.

Little Finger: extra sweet, orange to 3½ inches long; 65 days to harvest; open-pollinated.

Nantes Half Long: tender, sweet, fine-grained, nearly coreless, deep-orange to 6 inches long; 65 days to harvest; open-pollinated.

Purple Dragon: sweet, rich, purple skin, yellow core, to 6 inches long; 65 days to harvest; open-pollinated.

Chantenay: sweet, tender, reddish-orange to 6 inches long; good choice for heavy or shallow soils; 65 days to harvest; open pollinated.

Scarlet Nantes: sweet, juicy, fine-grained, coreless, orange-red to 6 inches long; 65 days to harvest; open pollinated.

St. Valery: sweet, tender, little core, bright reddish-orange to 10 inches long; 70 days to harvest; open pollinated.

Touchon: crisp, sweet, coreless, orange to 6 inches long; 65 days to harvest; open pollinated.

Do not overdose - your skin will turn yellow! - It's called Carotenemia! also called Hypercarotenaemia

One carrot (7 1/2" long) has 2025 RE of vitamin A, which is 203% of your Daily Value. One pound of carrots has 1276% of your RDA for vitamin A. Eat too many carrots in a day and you have probably saturated your body's ability to store vitamin A over a short time and so it is showing up as an orange tint on your skin. Consume too many carrots or drink too much carrot juice and your skin, mostly the hands, will turn yellowish-orange. There are two possible reasons why your skin turns orange. Either your body is unable to process all the carotene properly in the carrot juice you are drinking , or your liver is toxic. Either way, the colour shows up in your skin.

Yellow pigmentation in human skin may in some instances be due to jaundice but in others it may be due to no more than an unusually high consumption of carrots or other source of carotene. Hypercarotenaemia can be distinguished from jaundice by the fact that the sclerae retain their normal white colour. With so much public interest in cult diets and extreme forms of vegetarianism some individuals may develop a passion for eating carrots and may consume up to 4 lb (1.75 kg) daily.

Pigmentation occurs first on the palms and the soles of the feet and may extend to the nasolabial folds. The condition is harmless as the body converts carotene to retinol (vitamin A) only in amounts as required; hypervitaminosis A cannot, therefore, occur from over consumption of carotene. When patients who have developed a passion for eating carrots are told that the condition is not harmful some may prefer to remain yellow and go on eating them. If the patient wants the colour to be dispersed, however, he or she need only reduce the number of carrots eaten to an ordinary level, and the pigmentation will disappear within a few weeks. (Source: Hypercarotenaemia Author(s): Ivan M. Sharman - British Medical Journal (Clinical Research Edition), Vol. 290, No. 6462 (Jan. 12, 1985, pp. 95-96)

If you are having difficulty processing carotene:

You may be drinking too much carrot juice at once. Your body can't really assimilate more than 8-10 oz. of carrot juice at one time (taken on an empty stomach). So if you're drinking a bigger glass than that, you could be causing your own problem. Instead, try drinking no more than 8 oz. at a time. If you're trying to add extra carrot juice to your diet (possibly because you're fighting cancer and want the extra antioxidants), then drink 8 oz. of carrot juice and wait at least an hour before ingesting more. Your body can handle it at this rate and you shouldn't then be getting discoloured skin.

Carotenemia is the medical term for increased blood levels of the pigment carotene. Do not be fooled this is not a sign of good health. It signals excessive intake of carotene. This yellow-orange skin hue is a tell-tale sign of a beta carotene overdose from this hefty carrot/juice consumption. Beta carotene, along with other plant pigments generally called carotenes, found in carrots and other colourful vegetables and fruits, are a boost to your health - but like everything in life, only in moderation.  Yes, certainly eat plenty of vegetables, and in some cases, under strict medical supervision, eat large quantities of fruit and vegetables in place of poorer nutritional foods, and drinks.

Like many foods eaten in excess, carrots can produce unhealthy results too. Carotene, the pigment that gives carrots and other yellow fruits and vegetables their colour, can cause jaundice when consumed in excessive quantities. Some people who have imbibed large quantities of carrot juice in a relatively short time developed a yellow hue to their skin.

Though the yellowing of the skin from indulging in a heavy dose of carrots is seldom serious and will disappear in a few days, if consumption ceases, continued carrot gorging can cause medical problems. In 1974 one unfortunate English health advocate named Basil Brown consumed 10 gallons of carrot juice and took 10,000 times the recommended RDA of vitamin A in a period of 10 days. Those 10 days were the unfortunate man's undoing, his skin turned bright yellow and he died of severe liver damage, probably from the high intake of Vitamin A tablets.

Here is how the press reported the incident in 1974 - Extract from "The Times" - Times 15 February 1974

Carrot juice diet killed scientist

A health food addict who had been drinking up to eight pints of carrot juice a day was bright yellow when he died, an inquest at Croydon. Surrey, was told yesterday. Dr John Fabricius said he believed Mr Basil Brown' aged 48, a scientific adviser, had died of vitamin A poisoning. Mrs Brenda Brown, of Hayes Lane, Kenley, the dead man's wife, told Dr Mary McHugh, the coroner, that she had prepared the carrot juice. "Nobody pre- scribed it. He just thought it was the right way to eat. He also took vitamin A tablets."

A typical day's diet for her husband was: breakfast, carrot juice and fruit ; midday, more carrot Juice and fruit; evening meal, eggs, tomatoes, cheese. Dr J. Fabricius, the family's doctor, told the coroner that he had warned Mr Brown against his addiction to vitamin A. He had warned Mr Brown to stop taking vitamin A and had later sent him to a specialist who also warned him.

Mr Brown had been '"an intelligent man but he had a very low opinion of doctors ". Dr David Haler, a pathologist, said that Mr Brown was bright yellow when he died. Vitamin A poisoning, like alcoholic poisoning, produced cirrhosis of the liver. The inquest found that Mr Brown had died from carrot juice addiction.

The death of the 48 year old man was widely reported in the press some years ago. The coroner attributed death to addiction to carrot juice. In this instance, however, the dietary regimen that eventually proved fatal included not only large quantities of carrot juice but also up to six tablets of retinol acetate (up to 90 mg retinol) daily. A combined overdose of both retinol and carrots is most unusual. Possible addiction to carrots may have reduced the patients intake of more nourishing food

Eating carrots can become addictive:

Eating raw carrots may be as addictive as cigarette smoking, and every bit as difficult to give up, according to research on people who develop serious cravings for the vegetable. The phenomenon of 'raw carrot abuse' and the nervous disorders that come in its wake are described today in the British Journal of Addiction. Although it has been known since the early 1900s that excessive carrot intake can turn the skin orange, the psychological effects of such behaviour are only just coming to light.

One 35-year-old woman patient at a psychiatric clinic in Prague, who was eating a kilogram of raw carrots a day, had to be treated in hospital for 'neurological disturbance'. Another woman seen by the Ludek Cerny, author of the study, started consuming huge quantities of carrots while pregnant with her first child, and managed to stop for 15 years after the baby was born. The habit resumed after a stomach upset. 'Her desire became so intense that she preserved the peelings as a reserve supply. She resorted to purchasing and eating carrots secretly,' the report says.

Switching to radishes helped her reduce her dependency, and she now survives happily on a carrot-free diet.
The third case described in the study concerned a 40-year-old man who sought help to give up tobacco. 'His wife had advised him that it was necessary to replace cigarettes with something else and recommended . . . crunching some vegetables.
'He was soon eating carrots constantly, consuming up to five bunches a day, and as it was spring he put himself to considerable expense.' Unfortunately, although the man has kicked the carrot habit, he has resumed smoking.

The author suggests that the psychological dependence arises not only from the carotene contained in the vegetable, but possibly from some other active ingredient. 'The withdrawal symptom is so intense that the afflicted persons get hold of and consume carrots even in socially quite unacceptable situations.'
(source - http://www.independent.co.uk/news/uk/carrots-as-addictive-as-cigarette-smoking-1537344.html )

"The Orange Man and other Narratives of Medical Detection" (1965), a book by Berton Roueche reports the strange results of two cases presented at the University of Tennessee College of Medicine.

"The patients came in with bright orange skins. It turned out that they had been eating too many carrots (which contain carotene, a yellow pigment) and tomatoes (lycopene). The result was orange skins. How many carrots and tomatoes were too many? In one case it was 2 cups of carrots a day plus two tomatoes. When the excessive carrots and tomatoes were eliminated from the diet, the patient's skin returned to its normal colour with no ill effects." - (Source - The Orange Man and Other Narratives of Medical Detection by: Berton Roueche publisher: Little Brown & Company, ISBN-10: 0316759511 ISBN-13: 978-0316759519)

Pro-vitamin A is converted to vitamin A in the body. It is true that drinking more than five glasses of carrot juice per week may cause the skin to yellow slightly. This is simply a manifestation of the toxins that the liver is excreting. As an overall tonic and rejuvenator, carrot juice, in moderation, can't be beat.

The good thing about beta-carotene overdosing through over eating carotene rich foods is that the body doesn't convert the excess to vitamin A. If this were the case, serious toxicity problems, such as liver damage, would occur. Instead, the excess carotene accumulates over a period of weeks in the skin, primarily on the palms of hands and feet, lending a yellow-orange hue. There has never been a case where consumption of very large quantities of carotenoids has been shown to be toxic.

Consumption of Vitamin A in the form of retinol (in which case it would have come from an animal source) can be fatal if taken in large quantities. In the early days of polar exploration some of the adventurers made the mistake of killing polar bears and eating their liver. These explorers died as the result of Vitamin A poisoning. Even a small portion of liver from a polar bear can prove fatal because it contains so much Vitamin A in the form of retinol. Carotenoids on the other hand must be converted by the body into vitamin A. When the body converts what it needs the conversion process ceases and the body stores the carotenoids until needed at a future date

The amount of carotene that causes notable skin colour changes varies, but one study showed that approximately 50 milligrams daily led to discolouration in about 10 days. The skin discolouration is completely harmless, except perhaps to friends who may find this appearance startling.
While this orange skin is not a threat to health, the over-emphasis on one source of beta carotene, from carrots/juice, is a concern. You are missing out on health benefits from the family of carotenes and other phytochemicals by not eating a variety of vegetables (such as tomatoes, kale, spinach, winter squashes, broccoli and romaine lettuce) and fruit (including apricots, tangerines, watermelon, cantaloupe and grapefruit).

Remember that while excess carotene can often cause this condition in children, it is uncommon in healthy adults because their liver should function well enough to convert the beta-carotene to vitamin A and eliminate the rest from the body. As a rule, spinach juice won't turn you green, beets won't turn you red, carrots won't turn you orange. We usually get yellow / orange when we are jaundiced because our liver is congested or it is casting off toxins. The skin is one of four organs of elimination in your body. Some toxins will come out there. (Did you know the skin is the largest organ in the body?).

Carotenemia should not to be confused with lycopenemia , a similar condition - an excess of lycopene in the blood. The skin takes on the red colour found in tomatoes.

Read more about Vitamin A - Click here.      Find out more here about Carotenemia here.

Researchers prove the validity of carrot allergy

Allergic reactions to carrot and celery are very uncommon in the United States, however, reactions to carrots affect up to 25% of food-allergic individuals in Europe, and are associated with cross sensitivity to celery, certain spices, mugwort, and birch pollen. Several European researchers were recently able to prove the allergenicity of carrot for the first time in a study from the August Journal Allergy & Clinical Immunology. Barbara Ballmer-Weber, MD, and colleagues from University Hospital in Zurich, Paul-Ehrlich-Institut, Langen, Germany and the University of Vienna, sought to confirm sensitization to carrot by conducting several different tests on 26 patients with a history of allergic reactions to carrots.
Two food challenges were performed. The first was a double-blinded, placebo-controlled food challenge (DBPCFC), where subjects were given two different drinks: one was an active drink containing carrot and the other was a placebo drink. The second food challenge performed was a spit and chew test. The patients with a negative reactions in the DBPCFC chewed 5 g of raw carrot and spit it out. If they did not experience a reaction, they chewed and swallowed 5 g, then 10 g, and then 20 g of raw carrot. Skin tests and in vitro blood tests were performed to check for the presence of IgE, the antibody that produces allergic reactions. In vitro testing was also performed to see if allergic sensitivity to birch pollen initially triggered the sensitivity to carrots in these individuals.

In the first food challenge, researchers found that 20 patients reacted to the carrot-containing drink but not the placebo. Four patients responded to neither the carrot-containing drink nor the placebo drink. In the spit and chew test, three of these latter four subjects noted no symptoms. The fourth patient reported symptoms of oral allergy syndrome (itching of the throat and mouth) after swallowing 5 g of raw carrot. Researchers found that all patients who had positive DBPCFC's also had positive skin test results to raw carrot, while all patients who had negative DBPCFC's had negative skin tests and did not have subsequent reactions to the ingestion of carrot. Additionally, all of the carrot-allergic patients also had birch pollen specific IgE. However, in vitro testing of the serum from the carrot-allergic patients revealed that allergic binding could not be blocked by birch pollen proteins.

For the first time researchers were able to confirm carrot allergy in 20 of 26 European patients using DBPCFC protocol with carrot. Although these allergic patients produced IgE to both carrot and birch pollens, in vitro testing seemed to discount the theory that exposure to airborne birch pollen always precedes and predisposes allergic patients to the development of carrot allergies.
The AAAAI is the largest professional medical specialty organization in the United States representing allergists, asthma specialists, clinical immunologists, allied health professionals and others with a special interest in the research and treatment of allergic disease. Allergy/immunology specialists are pediatric or internal medicine physicians who have elected an additional two years of training to become specialized in the treatment of asthma, allergy and immunologic disease. Established in 1943, the Academy has more than 6,000 members in the United States, Canada and 60 other countries. The Academy serves as an advocate to the public by providing educational information through its Web site.  Click here to go there.

There is some evidence that people who are allergic to raw carrots are not allergic to cooked ones. This is because when carrots are cooked, the potentially allergenic proteins within them unravel, rendering them safe from targeting by the immune system. Read more here. Available to download in Word format from the Museum here.

EDITOR'S NOTE: These studies were published in the peer-reviewed, scientific journal of the American Academy of Allergy, Asthma and Immunology.

There are also cases of allergy to Carotene - read more here (Daily Express UK report)

Carrots and their leaves can cause dermatitis in sensitive skins. Read more here. Or download the extract report here.

Carrots have been known (rarely) to contain toxic chemicals: recent routine tests found unacceptably high levels of organophosphorus pesticides (used to kill the carrot fly) in some carrots. Peeling carrots and slicing off their tops removes virtually all of these residues. But beware that most of the goodness in carrots is in the skins. (see below)

Are Carrots better for you eaten raw or cooked? The answer is yes to both questions. Read on.

Are Carrots more nutritious in their raw state than when cooked?  - That's a very good question.

Opinions vary. Clearly a raw carrot has more goodness in it when it is raw and therefore you would assume it is the healthiest way to eat it. But unless the carrot is juiced then consumed, the body cannot break down the goodness because of the cellular nature of the carrot. Tests have shown that three percent of the total beta-carotene content is released from raw carrots when consumed in raw pieces. When homogenized (pulped) 21% was released. Cooking the pulp increased the accessibility to 27%. Addition of cooking oil to the cooked pulp further increased the released amount to 39%. (European Journal of Clinical Nutrition (2002) 56, 425–430- Estimation of carotenoid accessibility from carrots determined by an in vitro digestion method, Hedren et al)

Boiling carrots before slicing them increases their anti-cancer properties by 25%, a new study has revealed. Dr Kirsten Brandt, an agricultural scientist at Newcastle University, has discovered that the subtle difference between pre-slicing a carrot and boiling it whole could drastically affect the vegetable's nutritional powers. Carrots cooked without being sliced have one quarter more of the anti-cancer compound falcarinol than those that are chopped up first. An earlier study by Dr Brandt and colleagues at the University of Southern Denmark found that people whose diets were rich in falcarinol were around 30% less likely to develop cancer than those who ate none.  (Read full article here)

A substance called falcarinol that is found in carrots has been found to reduce the risk of cancer, according to researchers at Danish Institute of Agricultural Sciences (DIAS). Kirsten Brandt, head of the research department, explains that isolated cancer cells grow more slowly when exposed to falcarinol.

This substance is a polyacethylen, soluble in water  and therefore some falcarinol is lost during boiling, but not all of it. In further experiments (read here), it was found  that if they are boiled whole or steamed, the loss is approx. 30% (so there is still 70% in the carrot), while if they are cut into small pieces before boiling, the loss is much greater, more like 60% lost (40% retained in the carrots).

When they are boiled (using any method) the carrots are easier to digest, so it is likely that you take up more of the falcarinol in them (lose less of it in the stools). Due to this it is not possible to say if boiled is better or worse than raw, since a better bioavailability can easily make up for the 30% loss.

On balance, boiled (whole) is probably slightly better than raw, but that the difference is small, so what is important is that people should cook the carrots or not according to their preference rather that worry about science in this regard! - Eat more carrots!!

It has been proved that boiling and steaming better preserves antioxidants, particularly carotenoids, in carrots, than frying, though boiling was deemed the best. The researchers studied the impact of the various cooking techniques on compounds such as carotenoids, ascorbic acid and polyphenols.

Note: Cooked carrots weighed about 10% less than they did before being cooked, even when they were boiled in water. - from an academic study into nutritional properties of carrots after cooking. (Newcastle University (UK) 2009) - Full report here -  note - this is a bona fide UK Government website NHS=National Health Service.

Image, right, from World War Two advice in the UK, 1940.

Deep fried foods are notorious sources of free radicals, caused by oil being continuously oxidized when it is heated at high temperatures. These radicals, which are highly reactive because they have at least one unpaired electron, can injure cells in the body. The antioxidants in the oil and the vegetables get used up during frying in stabilizing the cycle of oxidation.

Another study in 2002 showed that cooking carrots increases their level of beta-carotene. Beta-carotene belongs to a group of antioxidant substances called carotenoids, which give fruits and vegetables their red, yellow, and orange colourings. The body converts beta-carotene into vitamin A, which plays an important role in vision, reproduction, bone growth and regulating the immune system.

The downside of cooking vegetables is that it can destroy some of the vitamin C in them. The reason is that Vitamin C, which is highly unstable, is easily degraded through oxidation, exposure to heat (it can increase the rate at which vitamin C reacts with oxygen in the air) and through cooking in water (it dissolves in water). 

So in reality, unlike most other vegetables (though not all), carrots are more nutritious when eaten cooked than eaten raw (except when juiced). Because raw carrots have tough cellular walls, the body is able to convert less than 25 per cent of their beta carotene into vitamin A.  Cooking, however,  partially dissolves cellulose-thickened cell walls, freeing up nutrients by breaking down the cell membranes.

A good rule to follow is - "We normally cook things to make them taste better; if they taste better we are more likely to eat them."

See the extract from the BBC video "The truth about raw carrots" -  here.

An experiment carried out at the Institute of Food Research in 2009 showed that the body can absorb about 5% of the beta carotene from a single carrot, whereas when it is boiled, the carrot released 60% and blended and then boiled a whopping 90%!!

So long as the cooked carrots are served as part of a meal that provides some fat the body can absorb more than half of the carotene. Also, it usual for Carrots to be cut into pieces and eaten after boiling or steaming, but done in this way, half the proteins and soluble carbohydrates will be lost so it is more advisable to cook them whole and then cut up.

Experiments show that eating lightly-cooked carrots is much more beneficial than eating raw carrots, which confirms the ancient wisdom in traditional Chinese medicine. Traditional Chinese medicine practitioners have always recommended that their patients eat lightly-cooked carrots in order to get the best nutritional absorption. Recent research by Dr. Xiangdong Wang at Tufts University shows that beta carotene can change in the human body into a substance called retinoic acid, which is widely used to treat cancers.

Carrots contain a lot of beta carotene, which may help reduce a wide range of cancers including lung, mouth, throat, stomach, intestine, bladder, prostate and breast. Some research indicated beta carotene may actually cause cancer, but this has not proven that eating carrots, unless in very large quantities - 2 to 3 kilos a day, can cause cancer. 

In fact, a substance called falcarinol that is found in carrots has been found to reduce the risk of cancer, according to researchers at Danish Institute of Agricultural Sciences (DIAS). Kirsten Brandt, head of the research department, explains that isolated cancer cells grow more slowly when exposed to falcarinol. This substance is a polyacethylen, the amount of falcarinol is slightly higher when eaten raw, but when you cook them it softens the tissues and makes it easier to get them out. You probably get more when you eat them boiled or steamed.

Eating raw carrots can help relieve and dissipate stress! - like chewing gum or a lot better.

Carrots are more nutritious when cut by a knife! - read here.

Microwaving may help retain more goodness -

Some vegetable cooking methods may be better than others when it comes to maintaining beneficial antioxidant levels, according to a new study in the Journal of Food Science, published by the Institute of Food Technologists. Results showed that, depending on the vegetable, cooking on a flat metal surface with no oil (griddling) and microwave cooking maintained the highest antioxidant levels. Fruits and vegetables are considered to be the major contributors of nutritional antioxidants, which may prevent cancer and other diseases. Because of their high antioxidant levels and low-calorie content, consumers are encouraged to eat several servings of fruits and vegetables daily. Researchers at the University of Murcia and the University of Complutense in Spain examined how various cooking methods affected antioxidant activity by analyzing six cooking methods with 20 vegetables.

The six cooking methods were boiling, pressure-cooking, baking, microwaving, griddling and frying.

Their findings showed the following:

• The highest antioxidant loss was observed in cauliflower after boiling and microwaving, peas after boiling, and zucchini after boiling and frying.

• Green beans, beets, and garlic were found to keep their antioxidant levels after most cooking treatments.

• The vegetables that increased their antioxidant levels after all cooking methods were green beans (except green beans after boiling), celery and carrots.

• Artichoke was the only vegetable that kept its high antioxidant level during all the cooking methods.

Griddle- and microwave-cooking helped maintain the highest levels of antioxidants, produced the lowest losses while “pressure-cooking and boiling led to the greatest losses,” says lead researcher A. M. Jiménez-Monreal. “In short, water is not the cook’s best friend when it comes to preparing vegetables.”

Editors note: This research is a little suspect as they have found some changes in the chemical reactivity, without any data indicating a correlation with the biological effect. They could just as well have measured the salt content.

The Food and Drug Administration (FDA) has regulated the manufacture of microwave ovens since 1971. On the basis of current knowledge about microwave radiation, the Agency believes that ovens that meet the FDA standard and are used according to the manufacturer's instructions are safe for use, read more.

Cancer Research UK has also researched the effecrts of radiation and microwaves and possible links to cancer, read more.

Goodness in the skin - As a rough guide the deeper the orange pigmentation in a carrot the more carotene. So peeling can take away some of the nutritional value (some carotene and some trace minerals), if only by volume (ie you are making a smaller carrot!) - . Up to 15% of the carotene! In fact the goodness tends to diminish as you approach the centre, aligned with the lighter colour; so one could put up an arguments for coring rather than peeling!  Hence "baby" carrots are usually less nutritious than whole ones. (They are shaved and abrasively tumbled). If you go to the USDA Nutritional database and compare raw carrots to baby carrots (which are peeled) you will see that the raw carrots have higher proportionate levels of Vitamin A and other nutrients.

The majority of the carotenoid content is contained in the Phloem (outer flesh). Source DISTRIBUTION OF CAROTENOIDS IN DIFFERENT PARTS OF THE CARROT BY V. H. BOOTH 1951, J. Sci. Food Agric., 2, August, 1951

There is some loss of carotene for baby carrots, relative to whole carrots, because the peeling process breaks cells which lose their contents, including carotenes. It's not that the outer layer (peel) of the root is much more nutritious but because of cell breakage for those cells, just below the skin, which are cut through in the process of peeling and scrubbing off the outer layers.

The fact that a carrot's peel and its nearby flesh are the same colour is an indicator that the two parts of the vegetable have a similar nutritional value. The Phloem (just beneath skin) has a higher concentration of carotenoids than the Xylem, which is evident from the relative colours of the two parts of the root. A diagram of the carrot root is shown here. This academic journal fully researched and reported thus:

"The concentration of total carotenoids in various sections of the root of the carrot was studied by extracting the fat-soluble yellow pigment and estimating it colorimetrically. The concentration had a general fall longitudinally from crown to tip although there was a small increase just beyond half-way. The side roots and the ‘rat-tail’ root had relatively very low concentrations of carotenoids.

The pigmentation of xylem was always less, and varied much more, than that of the phloem but the two were positively correlated. Carotene comprised about 70% of the total carotenoids in the xylem and this percentage was positively correlated with depth of pigmentation. The concentration of carotenols in xylems of different carrots was much more nearly constant than that of carotene."

(above) Source - Distribution of carotenoids in different parts of the carrot 1. V. H. Booth - Journal of the Science of Food and Agriculture Volume 2, Issue 8, pages 350–353, August 1951

Yet another gave more information on this subject:

"Carrots contained mainly hydroxycinnamic acids and derivatives. Among them chlorogenic acid was a major hydroxycinnamic acid. Phenolic content in different tissues decreased from peel, phloem to xylem, while antioxidant and radical scavenging activities in different tissues decreased in same order as the phenolic content and correlated well with total phenolic contents. All phenolic extracts presented stronger radical scavenging ability than pure chlorogenic acid, vitamin C and β-carotene.

Therefore, we suggest that phenolics could play an important role in antioxidant properties in carrots and other hydroxycinnamic derivatives such as dicaffeoylquinic acids in the extracts may exert some strong antioxidant activities along with chlorogenic acid. The higher level of phenolics and antioxidant properties in carrot peel treated as the waste in the processing industry could be considered for value-added utilization."

(above) Source - Journal: Food, Agriculture and Environment (JFAE) Print ISSN:1459-0255 Online ISSN: 1459-0263 Year: 2004, Vol. 2, Issue 1, pages 95-100.

The Carrot museum recommends you just need to scrub and rinse carrots really well to get rid of the dirt or blemishes. Some people think that pesticides are concentrated in the peel of conventional carrots, but that's not the case. Since carrots are grown underground, the chemicals get into the soil and can seep into the entire vegetable, so peeling won't necessarily prevent you from consuming pesticides.

Bitterness in the skin - A study published in 2007 showed that conducted by Danish researchers, a carrot's bitterness is largely concentrated in its peel.

“The present study demonstrated that the peel from raw carrots contained higher concentration of the polyacetylenes falcarindiol (FaDOH) and falcarindiol 3- acetate (FaDOAc) and the isocoumarin 6-methoxymellein than the peeled root. Investigation of bitterness revealed that high sugar content to some extent could mask the bitter perception in carrots.” Full study here. (Investigation of bitterness in carrots (Daucus carota L.) based on quantitative chemical and sensory analyses Stine Kreutzmann - Science Direct LWT 41 (2008) 193–205)