DESCRIPTION

Beta carotene is found in the yellow or orange pigment present in many fruits and vegetables. The human body can readily convert beta carotene into vitamin A.

In 1830, the yellow pigment in carrots was isolated and named carotene, however, it was not until 1919 that the connection between carotene and vitamin A was known.

It is now known that people with high levels of beta carotene in their diets have less chance of developing certain types of cancers than those with a lower intake of the nutrient.

BENEFITS

In addition to all the functions for vitamin A, beta carotene is thought to be a free radical quencher. This means it has the capacity to protect delicate cell contents from damage.

MEASUREMENT

International units (iu) of beta carotene should not be confused with ius of vitamin A activity. (Only iu’s of vitamin A have scientific meaning.) Iu’s of beta carotene divided by three gives iu’s of vitamin A activity, so a traditionally labeled 25,000iu (15mg) beta carotene supplement will provide the body with 8,333 iu of vitamin A.

REQUIREMENTS (RNI)

As dietary beta carotene contributes towards total vitamin A intake – there is not separate requirement for beta carotene.

BEST FOOD SOURCES

BETA CAROTENE PROVIDING VITAMIN A

WHO MAY NEED TO SUPPLEMENT

Many studies now show that low intakes of beta carotene are associated with the development of cancer and heart disease. With this in mind, nutrition experts underline the importance of taking two to three good portions of fruit and vegetables daily. If this sort of dietary level is not being achieved, a supplement of beta carotene may be advisable.

Beta carotene supplementation is also recommended before prolonged exposure to hot sun. It can help to protect the skin from ultraviolet induced damage and may even protect against skin cancer in the long term.

Beta carotene acts as an antioxidant, trapping and neutralizing single oxygen molecules and other free radicals, which can damage the body’s cellular membranes, lipids, proteins and vitamins. In addition, beta carotene enhances the immune system by stimulating the activity of interferon.

Cancer, atherosclerosis, diabetes, cataracts, and many other chronic degenerative diseases have been linked to free-radical damage. Numerous epidemiological studies and clinical trials have shown that people consume high quantities of beta carotene have a lowered incidence of cancer and other chronic diseases.

SAFETY

Beta carotene is an extremely safe form of taking vitamin A, because at very high levels of beta carotene intake, the body’s beta-carotene-to-vitamin-A conversion process slows down dramatically. Deficiency symptoms of beta carotene are the same as for vitamin A.

The only known side effect occurring with high levels of beta carotene is "carotenemia," a harmless condition in which the skin turns a slight orange color. This is reversible upon stopping beta carotene supplementation. Carotenemia may occur at dosages of approximately 30mg daily and above.

INTERACTIONS AND CONTRAINDICATIONS

Beta carotene cannot be properly converted into vitamin A by diabetics or those with hypothyroidism or severe liver malfunctioning. These people should therefore not rely on beta carotene as a source of vitamin A activity.