HEALTH BENEFITS OF CARROTS

Carrots are root vegetables of the Daucus carota plant. Their signature colour is orange, though through domestication, different cultivars exist in colours such as black, purple, white, red, and yellow. Carrots are believed to have originated from Central Asia, but today they are widely cultivated and consumed all over the world (1).  

Carrots can be washed and eaten raw as fruits are eten, or added to salads, or used as relishes. Carrots can also be processed into canned carrot slices, carrot juices, carrot concentrates, carrot pickles, or carrot cakes (2). And if you are growing your own carrots this year, they are even more nutritious and better for you, as they are most likely to be organic and taste delicious as they are grown by you.

Nutrition Profile

Besides their great taste and a wide variety of uses, carrots do have an impressive nutritional profile. A 100g serving of raw carrots offers the following (3).

• Energy: 41 calories
• Water: 88.3g
• Protein: 1g
• Carbohydrates: 9.6g
• Fat: 0.2g
• Fiber: 2.8g
• Vitamin A: 835µg (104% DV)
• Vitamin K: 13.2µg (11%)
• Vitamin C: 5.9mg (7% DV)
• Potassium: 320mg (6% DV)

The DV (daily value) is the recommended quantity of nutrient a person is expected to consume every day or expected to not surpass every day. Hence, the percentage daily value (% DV) of a particular nutrient in a food indicates how much that nutrient per serving of that food or food product contributes to our diet. When the % DV is 5% or less, the nutrient’s contribution from that food to the diet is said to be low, whereas when the % DV is 20% or more, the nutrient’s contribution is said to be high (4). 

The Health Benefits of Carrots

Promotes good eye sights

Carrots are an excellent source of vitamin A as a 100g serving of carrots provide for 104% of that daily value for vitamin A (3). Vitamin A is an important fat-soluble vitamin that plays a very crucial role in ensuring good vision. It is needed to produce rhodopsin, a pigment that is found in the retina of the eyes (5).

Rhodopsin is extremely sensitive to light and hence very useful in dim environments. In other words, rhodopsin is responsible for helping people see better in dim light or in the dark or at night. This is the reason why people who are deficient in vitamin A do not see well at night or under dim light, a condition called nyctalopia or night blindness (5, 6).

Night blindness is always the first sign of vitamin A deficiency, which if not remedied can lead to cone dysfunction and daytime vision impairment. It can make the cornea very dry resulting in damage to both the cornea and the retina of the eyes. Vitamin A deficiency is one of the leading causes of blindness in the world today, especially in developing countries. It is the leading cause of blindness in children and the WHO (World Health Organization) reports that an approximate 250,000 – 500,000 children go blind yearly because of vitamin A deficiency. Of this number, half of them end up dying within one year of losing their sight (5, 7).

Besides vitamin A, carrots also contain the colored pigments lutein and zeaxanthin, that are reputable for enhancing good vision. They absorb blue light that is very reactive and can cause oxidative damage to the most sensitive layers of the eye’s retina (8). Moreover, lutein and zeaxanthin are very potent antioxidants, that scavenge and quench free radicals, preventing damage to the macula caused by oxidative stress. Furthermore, they act as filter, prefiltering light and increasing the contrast of both objects that we focus on and their backgrounds which helps us see better (9).

Can help with blood sugar management.

Carrots have a low glycemic index (GI), with the GI for raw carrots being 16 and that of boiled carrots ranging from 35 to 43. The glycemic index is a measure of how fast and how high certain foods or drinks raise a person’s blood sugar (glucose) level. The GI runs on a scale from 1 to 100, with 100 being the GI of glucose. The GI is grouped and interpreted as follows (10, 11).

• Low glycemic index: 1 – 55
• Medium glycemic index: 56 – 69
• High glycemic index: 70 or more

Looking at the GI grouping, carrots do fall in the group of low glycemic index foods, meaning that eating carrots will not cause rapid spikes in blood glucose levels which is very beneficial for managing blood sugar levels in diabetics or prediabetics.

This could be explained by the fact that carrots do not contain a lot of carbohydrates, with only 9.6g of carbohydrates per 100g serving. Besides, of these few carbohydrates, a good quantity is fiber. Carrots contain 2.8g of fiber per 100g serving of carrot (which is equal to 12% DV for women and 8.2% DV for men), making carrots a good source of dietary fiber (3). 

Dietary fiber in carrots dissolves in water forming a thick viscous gel that retards the emptying of food from the stomach. This slows down the digestion of nutrients and consequently, their absorption into the blood stream. As such there is a slow release of glucose into the blood stream at a steady rate which does not cause a rapid increase in blood sugar levels (12).

Can help lower blood pressure

Carrots contain a small amount of potassium (%6 DV), which can help the body lower blood pressure. Potassium reduces blood pressure by flushing sodium out of the body via urine, thus balancing the effect of sodium. Sodium pulls water into the blood stream, and so too much sodium in the blood implies much more water will be pulled into the bloodstream, increasing the volume of blood and inevitably the pressure of the blood flow. Potassium also helps reduce tension in the walls of the blood vessels which further contributes to lower blood pressure (13, 14).

Research studies have demonstrated that the classic western diets, which are commonly low in potassium, typically increase salt sensitivity and blood pressure (15).

Are good for weight loss and/or weight management

Carrots are low calorie foods, with only 41 calories per 100g serving. They make a healthy substitute for highly processed snacks that are loaded with calories. Besides, carrots contain plenty of water, with about 88g of water per 100g serving. So, eating raw carrots can help fill you up quickly, enabling you reduce calorie intake from other foods (3).

In addition, the soluble fiber in carrots retards the emptying of food from the stomach and earlier mentioned. This will keep you feeling fuller for longer, helping you cut down calorie intake. Thus, the water in carrots helps you fill up quickly, and the fiber in them keeps you full for longer. These functionalities about carrots make them an absolute must include in any weight loss or weight management plan (12).

The frequent consumption of carrots has been associated with reduced body mass index (BMI) and obesity in some research studies (16).

Can lower the risk of developing cancer

Carrots are rich in colored compounds called alpha carotene and beta carotene which enhance them with cancer fighting abilities. Epidemiological studies have demonstrated a correlation between high beta carotene levels in the blood and low incidence of cancers (17).  Some studies have shown a significantly strong negative correlation between developing lung cancer and alpha carotene intake (18).

Other bioactive compounds in carrots that have also been proven by research studies to combat cancer are polyacetylenic oxylipins. Falcarinol (FaOH) and falcarindiol (FaDOH), are the two major types of polyacetylenic oxylipins, that combat cancer by inhibiting proliferation of cancer cells and inflammation (19).

An inflammation is the body’s normal response to injury, during which the immune cells of the body produce chemicals to kill pathogens. Chronic inflammation that happens when the body’s mechanisms to shut down inflammatory responses fails becomes dangerous to the body. This is because the excess chemicals released to kill pathogens become damaging to the DNA of normal cells, which intend increases cell mutations and proliferation. This creates a very conducive environment for the development of cancer. So, the anti-inflammatory properties of these bioactive compounds help to inhibit the onset of chronic inflammation and thus cancer development (20).

Furthermore, lutein in carrots has been proven to show anti-cancer activities against breast cancer, and some types of kidney and bladder cancers. In breast cancer, lutein induces cell cycle arrest and apoptosis (cell death) of cancer cells which significantly prevents the growth of breast cancer cells (21).

Helps with proper growth, development and reproduction

Vitamin A in carrots plays a key role in ensuring proper growth and development of many body organs and cells. It increases the production of white blood cells that are necessary for strengthening the body’s immunity (22).

It also play a vital role in bone remodeling, the process of removing mature bone tissue from the skeleton, for the formation of new bone tissue. Bone remodeling is a lifelong process that protects the skeletal system’s structural integrity. It controls the reshaping of the bone following micro-damages that occur during normal activity, as well as after serious injuries like fractures (23).

Besides, bone remodeling also helps the body metabolically to balance calcium and phosphorus. The calcium to phosphorus ratio is essential for both bone growth and development in infants. Proper bone mass accumulation at the infancy stage is necessary to prevent poor growth in childhood and osteoporosis in adulthood (24).

Furthermore, vitamin A assists with the maintenance of healthy endothelial cells. These are cells that line up all blood vessels and the heart (23). They regulate exchanges that occur between the bloodstream and the tissues in the surrounding. Endothelial cells produce and release substances like nitric oxide and arachidonic acid, that control vascular contraction and relaxation, eventually controlling blood flow. They also release enzymes that control immune function, blood clotting and platelet adhesion (sticking of platelets to the site of damage to control bleeding) (25).  

In addition, vitamin A is needed to control the growth and division of cells during reproduction. It helps cell differentiation, which is vital for the formation and maintenance of important body organs like the eyes, heart, and lungs (26). Vitamin A deficiency during pregnancy succumbs the embryo to gross heart abnormalities and is aborted.  It can also result in anorectal malformations which can affect the development of the enteric nervous system (27).

Boosts body immunity

The body requires vitamin A for adaptive immunity and for the development of the cells that function in the adaptive immune system. These cells are the B-cells (which separate into plasma cells to make antibodies) and T cells (which are antigen specific). The adaptive immune system functions by first recognizing foreign antigens, and then generating pathogen-specific pathways to eliminate the particular pathogens or cells infected by the pathogen. Lastly, the system develops an immunological memory, so that in case of subsequent infection by that specific pathogen, they can be rapidly eliminated (28).  

Besides vitamin A in carrots, vitamin C is also involved in the enhancement of body immunity. Unlike vitamin A, vitamin C is involved in supporting both adaptive and innate immune systems of the body. The innate immune system is the body’s first line of shield or defense against pathogens. It is a more general response and does not specifically target any particular antigens. The white blood cells involved with innate immunity are phagocytes and lymphocytes, which all need vitamin C for both their production and function. They migrate to the site of infection, swallow up and kill the invading pathogens (29).

Hence, carrots supplies both vitamin A and C that function to support both the adaptive and the innate immune system of the body. As such, deficiencies in any or both vitamins can significantly increase a person’s susceptibility to infections.   

Carrots are a superfood, and certainly a must include in any healthy diet plan. However, it should be noted that moderation is key as with every other food. Eating too many carrots can cause a yellowing of the skin (because of too much beta-carotene). It is usually harmless and can be treated (30).

Also, some people might experience mouth itch, if they are allergic to certain proteins from fruits and vegetables. This is called oral allergic syndrome, and it is like pollen allergy. It only happens with raw carrots, so such people are advised to consume their carrots cooked (30).

Lastly, people suffering from hypothyroidism should watch eating too many carrots as they may not be able to convert beta-carotene to vitamin A (30).

REFERENCES

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