The pigments that give some fruits and vegetables their rich red, orange and yellow colours are called carotenoids. These natural compounds are also potent disease fighters. If your diet doesn't contain enough of them, supplements are a handy option.
What they are?
Although more than 600 carotenoid pigments have been identified in foods, it appears that only six are used in significant ways by the blood or tissues of the body. Besides beta-carotene, which is probably the best-known carotenoid, these include alpha-carotene, lycopene, lutein, zeaxanthin and cryptoxanthin.
Carotenoids are found in various fruits and vegetables, but the foods that are the most concentrated sources may not be part of y our daily fare. Alpha-carotene is found in carrots and pumpkin; lycopene is abundant in red fruits, such as watermelon, red grapefruit, guava and, especially, processed tomatoes. Lutein and zeaxanthin are plentiful in dark green vegetables, pumpkin and red capsicums; while cryptoxanthin is present in mangoes, oranges and peaches. Supplements providing a mixture of the six key carotenoids may be the best option.
What they do?
The primary benefit of carotenoids lies in the antioxidant potential. Antioxidants are compounds that protect body cells from damage by unstable oxygen molecules called free radicals. Although the carotenoids are similar, each acts on a specific type of body tissue. In addition, alpha-carotene and cryptoxanthin can be converted into vitamin A in the body, but not to the same extent as beta-carotene.
Carotenoids may guard against certain types of cancer, apparently by limiting the abnormal growth of cells. Lycopene, for instance, appears to inhibit prostate cancer formation. Researchers at Harvard University found that men who ate 10 or more servings a week of tomato-based foods – tomatoes are the richest dietary source of lycopene – cut their risk of prostate cancer by nearly 45%. Lycopene may also be effective against cancers of the stomach and digestive tract. Studies show that high intakes of alpha-carotene, lutein and zeaxanthin decrease the risk of lung cancer, and that cryptoxanthin and alpha-carotene lower the risk of cervical cancer.
In addition, carotenoids may fight heart disease. In a survey of 1300 elderly people in the US, those who ate the greatest amount of carotenoid-rich foods had half the risk of developing heart disease and a 75% lower risk of heart attack than those who ate the least of these foods. This was true even after the researchers took other heart-disease risk factors-such as smoking and high cholesterol levels-into account. Scientists believe that all carotenoids, particularly alpha-carotene and lycopene, block the formation of LDL ('bad') cholesterol, which can lead to heart attacks and other cardiovascular problems.
The carotenoids lutein and zeaxanthin promote clear vision by absorbing the sun's harmful ultraviolet rays and neutralizing free radicals in the retina (the light-sensitive portion of the eye). This may help to reduce the risk of macular degeneration, an age-related vision disorder that is the leading cause of blindness in older adults. Other carotenoids may prevent damage to the lens of the eye and so decrease the risk of cataracts.
Preliminary studies also indicate that there may be a link between low levels of carotenoids and menstrual disorders. And other studies show that, even after the onset of cancer, a diet high in carotenoids may improve the prognosis.
- May lower the risk of certain types of cancers, including prostate and lung cancer.
- May provide protection against heart disease.
- Slow down the development of macular degeneration.
- Enhance immunity.
- Soft gel.
- Reminder: If you have a medical condition, talk to your doctor before taking supplements.
How to take it?
If you don't eat a wide variety of foods rich in carotenoids, take a supplement that contains mixed carotenoids – alpha-carotene, beta-carotene, lycopene, lutein, zeaxanthin and cryptoxanthin – and supplies a minimum of 25000 IU vitamin A activity each day. Higher doses of mixed carotenoids may be recommended for the prevention of specific disorders.
Guidelines for use:
Take carotenoid supplements with foods that contain a bit of fat, which helps the body absorb the carotenoids more effectively. Some experts also believe that your body will absorb more of these nutrients if you divide the total daily amount of carotenoids you plan to take in half and have them at two different times during the day.
Possible side effects
Large doses of carotenoids (through food or supplements) can make your skin turn orange, especially the palms of your hands and the soles of your feet. This effect is harmless and will gradually go away if you reduce your intake of carotenoids. Though there are no other known side effects associated with large amounts of mixed carotenoids, taking high doses of individual carotenoids may interfere with the workings of the other carotenoids.
Facts and Tips
- Women who take oral contraceptives and post menopausal women who use oestrogen-based hormone replacement therapy have reduced levels of carotenoids in their blood. A mixed carotenoid supplement may be worthwhile for women in both groups.
- Cooked tomatoes contain less water than raw ones, and consequently more lycopene. And some experts think that using olive oil when cooking tomatoes enables the lycopene to be better absorbed.
- In a major European study, lycopene was shown to help prevent heart attacks. Men who consumed large amounts of lycopene had only half the risk of a heart attack of men who consumed small amounts. Lycopene's protective effect was most beneficial to nonsmokers.
Did you know?
Dark green vegetables also contain carotenoids. The green chlorophyll masks the yellow-orange pigments that they contain.