Essay/Term paper: Beta carotene

Essay, term paper, research paper:  Science Reports

Beta Carotene


Beta-carotene is a member of the carotenoid family and has over 500 relatives.
Carotenoids are yellow-to-red pigments found in all green plant tissues and in
some species of algae. So far 21 different carotenoids have been found in human
blood. The most abundant ones are alpha-carotene, beta-carotene, lutein,
lycopene, cryptoxanthin and zeaxanthin. A molecule of alpha-carotene, beta-
carotene, or cryptoxanthin can be split into two molecules of vitamin A in the
body but the conversion of beta-carotene is by far the most effective. The six
carotenoids are all antioxidants. They are very effective in neutralizing a
highly reactive for of oxygen called singlet oxygen but also, to some extent,
act to break up the chain reactions involved in lipid peroxidation. Numerous
studies have shown that people who consume a diet rich in dark yellow orange
vegetables (carrots) and dark green vegetables (broccoli) are much less likely
to develop cancer and heart disease. It has also been established that people
with low levels of beta-carotene in their blood have a higher incidence of heart
disease and cancer, particularly lung cancer. The National Cancer Institute
endorsed a study which found that women who consume lots of beta-carotene rich
fruits and vegetables have a lower chance of getting cancer, including breast
cancer. The Institution says that regularly eating lots of fruits and
vegetables plays a key roll in cancer prevention, but whether the preventative
action comes from beta-carotene or other nutrients in the produce has yet to be
determined. For people who don't like eating their fruits and vegetables, a
beta-carotene supplement pill was introduced into the market. Millions of
vegetable hating Americans hoped that by taking a pill instead of eating
vegetables, they could get the same rewards as their counterparts who enjoy the
taste of fruits and vegetables. But officials at the National Cancer Institute
released the results of two large studies designed to put the benefits of beta-
carotene supplements to the test. One followed 22,071 doctors who for 12 years
smokers had to be stopped prematurely because it seemed to me making the rate of
death from cancer and heart disease worse. Taking a simple chemical supplement
is not the same as eating a vegetable. Scientists suspect there are other
natural ingredients that work with vitamins to promote health. It is also
possible that a beta-carotene supplement derived from natural sources and
formulated so as to preserve the normal carotene ratio in the blood may be of
benefit for people at high risk for cancer and cardiovascular disease. This,
however, needs to proven. So, until the remaining riddles in the carotene
puzzle are solved, the prudent course of action is to avoid smoking and exposure
to second-hand smoke and to increase the intake of vegetables and fruits. In
1981 it was suggested that beta-carotene is the active component in the
protective vegetables and that supplementing with beta-carotene might prevent
certain cancers. The idea was based on the fact that took 50 mg of beta-
carotene every other day. Another involved 18,314 smokers, ex-smokers, and
asbestos workers. Not only did beta carotene produce no measurable health
benefits, but the study of beta-carotene is an antioxidant and the most abundant
carotenoid in vegetables. There was also considerable evidence to the effect
that vitamin A prevents or retards certain cancers, so that beta-carotene is
readily converted to vitamin A in the liver and intestine was seen as an added
bonus. More recent research suggests that beta-carotene's prevention effect is
due to its antioxidant property rather than to its ability to form vitamin A.
People need to learn to take a little bit of time to eat good, healthy foods
instead of relying on pills. I feel that more people need to be educated about
what beta carotene can do for you. If more people ate enough beta-carotene,
maybe doctors would have less patients to treat. Beta-Carotene really can help
prevent a lot of diseases. It's almost like a natural life-saver. Now I
understand why my parents are always telling me to "eat my vegetables, they are
good for you."

SOURCES

1. "Beta-Carotene: A Nugget of Nutritional Gold.", Marilyn Carnell, Ph.D., R.D
Better Homes and Gardens, October 1992: 64-66.

2. "Beta No More", Christine Gorman. Time Magazine, Jan. 29, 1996: pg. 66.

3. Peto , R, et al. Can dietary beta-carotene materially reduce human cancer
rates? Nature, Vol. 290, March 19, 1981, pp. 201-208.