Beta carotene
What is beta-carotene?
Beta-carotene provides the characteristic colour of carrots, winter squashes and cantaloupes, but it can also be found in egg-yolk. This compound belongs to the large group of carotenoids (which is also its name-giver), and its basis is the so-called isoprene structure. Beta-carotene is the provitamin for vitamin A. It means it is converted into vitamin A (retinol), which the organism can utilise.
Carotenoids was separated as early as in the 19th century, and it has been produced since the 50’s for manufacturing food colourings from it.
What foodstuffs provide it?
Everyone is quick to answer: carrots. Yes, true, but it can also be found in almost all the colour vegetables, mainly in yellow and red ones, but also in tree leaves. Yet, chlorophyll that is green covers the typical yellow colour, which though appears in autumn when chlorophyll decomposes. Below is the beta-carotene content of some fruits and vegetables:
- carrot 6,6 mg
- spinach 4,9 mg
- broccoli 1,5 mg
- mango 2,9 mg
- peach 0,5 mg
- cantaloupe 2,0 mg
What role does it play?
If you eat lots of carrots, you’ll whistle great – goes the saying. It might be true, but the benefit of beta-carotene is not limited to this only. Beta-carotene is the most important source of vitamin A, because the organism converts it into this vitamin, and stores the surplus. The organism converts beta-carotene into vitamin A according to need (a unit of vitamin A is created from 6 units of beta-carotene). Vitamin A is important for good vision and healthy mucous membranes, but as it is fat-soluble, its overdose can be toxic which is also true to dietary vitamin intake, so beta-carotene consumption is safer. One of the first symptoms for vitamin A deficiency is night-blindness. If retinol (Vitamin A - required for the functioning of retina’s light and colour perceiving receptors) is not available, the eye is incapable of adjusting to poor light. In the case of vitamin A deficiency, a single carrot a day might be sufficient to restore vision at night. In the developing world, vitamin A deficiency is the most frequent reason for blindness in the population below 21 years of age. Carotenoids act as antioxidants, so they can also reduce the risk of particular types of cancer. According to certain trials, the number of lung, skin, stomach and colon cancers can be reduced with a diet rich in beta-carotene. Beta-carotene is used as the colouring for margarine, butter, ice cream and soft drinks. Its benefit over other colourings is that it is organism-friendly.
Study findings
Studies indicate that carotenoids reduce the incidence rate of cardiovascular diseases and have a beneficial effect on the cholesterol level. A higher dose of beta-carotene taken combined with vitamin C plays a role in preventing cataract. According to particular studies, in ethnic groups the diets of whom contain fruits and vegetables rich in carotenoids, the incidence rate of malignant tumours, especially lung cancer is much lower. Dietary beta-carotene has been found to reduce the number of epithelial-related – lung, skin, cervix, respiratory track, stomach and colon tumours in high quantity. American researchers examined several groups of people. The likelihood of the formation of lung cancer was 4 times higher among those in the blood samples of whom the carotene level was the lowest in comparison to others, even though the difference between the two groups was as little as the beta-carotene content of one carrot a day! In a different trial, the link between dietary habits and lung cancer had been monitored on a sample of 2000 persons for 19 years. Among men having been smoking for 30 years, whose beta-carotene intake was on average the lowest, the risk of the formation of lung cancer was 8 times higher compared to those with the highest intake. A similar data was found among those who had not been smoking for years. Nutrition with high carotene content can also be connected with a lower incidence rate of the cancer of the pancreatic gland, larynx, oesophagus, prostate gland and urinary bladder.
