It appears that our organism uses only six out of 600 known carotenoid pigments. Apart from the well known beta-carotene, they are alpha-carotene, cryptoxanthin, lycopene, lutein and zeaxanthin.
Carotenoids are found in various fruits and vegetables, but foods with the highest concentrations may not be on your menu. Alpha-carotene is found in carrots and pumpkin, lycopene in red fruit (watermelon, red grapefruit and guava, and especially in cooked tomatoes). Large amounts of lutein and zeaxanthin can be found in dark green vegetables, puddings and red paprika; cryptoxanthin is in mangos, oranges and peaches. For a good effect in preventing the disease it is desirable to take dietary supplements containing a mixture of all six carotenoids.
How do they work?
The main beneficial effect of carotenoids comes from their antioxidant activity. They protect the cells of our body from the harmful effects of unstable oxygen molecules – free radicals. Although carotenoids are similar, each of them acts on different tissues in the body. In addition, alpha-carotene and cryptoxanthin may cross into vitamin A, but not as much as beta-carotene.
PREVENTION: carotenoids can provide protection against some types of cancer by limiting cell growth. Thus, for example, lycopene slows down the onset of prostate cancer. Research at Harvard University has shown that people who eat food with tomato (which is the richest source of lycopene), 10 or more times per week, reduce the risk of developing prostate cancer by almost 45%. Lycopene has a potential effect on the gastric and digestive system. Studies also show that high intake of alpha-carotene, lutein and zeaxanthin reduces the risk of lung cancer, while alpha-carotene and cryptoxanthin have such an effect on cervical cancer. Carotenoids also help in preventing heart diseases.
In a study conducted on 1,300 elderly people, people who consume the most nutritionally rich carotenoids, compared to those who eat the least of those foods, have half their chance of developing heart disease and 75% less chance of heart attack. These data also apply when considering other factors of risk for heart disease, such as smoking and high cholesterol levels. Scientists believe that all carotenoids, especially alpha-carotene and lycopene, prevent the formation of LDL (”bad”) cholesterol, which can cause infarct and other heart and blood vessels diseases.
ADDITIONAL USEFUL EFFECTS: lutein and zeaxanthin are important for healthy eyes. Other carotenoids can have a positive effect on the eye because they reduce the risk of some diseases, such as cataract. The research has confirmed the protective effect of lycopene against the oxidative damage of the human eye lens and reduced incidence of cataract in the examined animals. A study on 372 elderly patients showed the lowest risk of cortical cataracts in people with the highest level of lycopene in the blood.
A recent study suggests that increased lycopene intake, up to 15 mg per day (from tomato sauce), over the course of ten weeks, provides significant protection from sunburns caused by UV rays, although this protection is slow to develop. Of course, lycopene should not be used as a substitute for sunscreens.
How to take them?
DOSAGE: if you do not eat a lot of food that contain carotenoids, choose products with a mixture of all 6 mentioned carotenoids.
USE GUIDELINES: carotenoids should be taken with food that contains some fat, as they are more effectively absorbed that way. If you split you daily dose of supplements into two parts and drink them at a different time, your organism will absorb a larger amount of carotenoids.
Possible side effects
Consuming big doses of carotenoids, either from food or dietary supplements, can cause skin yellowing, especially on palms and thighs. This effect is harmless and eventually disappears with reduced intake. Although there are no other known side effects associated with the use of large doses of mixed carotenoids, intake of large amounts of one carotenoid may interfere with the effect of the other. It appears that dietary supplements that contain only beta-carotene do not reduce the risk of any disease; those dietary supplements can also worsen the condition of people with high risk of lung cancer.
IMPORTANT: pregnant women should avoid carotenoids, especially large doses.