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Carotenoids are phytonutrients, the nutritional elements
that give fruits and vegetables their distinctive colors,
odors and tastes. Although beta-carotene may be the
best-known and most abundant dietary carotenoid,
approximately 500 carotenoids have been identified and their
health benefits ate beginning to be recognized. Carotenoids
act as antioxidants, popularly thought of as anti-disease
and anti-aging nutrients.
Antioxidants help form the body’s defense against free
radicals. Free
radicals are not inherently bad (they help us generate
energy and fight
infections), but too many free radicals cause cells to age
prematurely. Our bodies are being exposed to more and more
free radicals, as they are dangerous byproducts of our
environment-air pollution, cigarette smoke and dietary fats.
While free
radicals can cause or complicate many diseases-including
cancer, arthritis, cataracts and heart disease-antioxidants
can help protect the body from these chronic disorders. They
also enhance the body’s immune system.
It is also
becoming clear that the best-known antioxidants (vitamins C
and E and beta-carotene) do not provide a complete defense
against free radicals. A combination of antioxidants works
better than single
antioxidants to enhance the body’s defense against free
radicals.
Increased amounts of carotenoids do not cause any toxic side
effects,
because excess carotenoids are used only as antioxidants, to
help the body maintain health. Thus, individuals can
increase their protection against certain diseases without
risk by increasing their intake of carotenoids. The
following information has been compiled to answer your
questions about these important nutrients.
What are
carotenoids?
Carotenoids are the substance that give fruits and
vegetables their orange, yellow and red colors. Green leafy
vegetables are also high in caroten-oids, but the color is
masked by chlorophyll.
For many
years the benefits of carotenoids were not known. However,
recent research suggests that carotenoids offer an army of
health benefits, such as lowering the risk for heart disease
and certain types of cancer, enhancing the immune system and
protecting us from age-related macular degeneration, the
leading cause of irreversible blindness among adults.
In addition
to beta-carotene, a number of other carotenoids have been
identified for their important roles as antioxidants in the
body. Alpha-carotene, for example, may be 10 times more
powerful than beta-carotene in protecting the body from
skin, eye, liver and lung damage. And the emerging body of
scientific evidence shows that other types of carotenoids
such as lutein, cryptoxanthin and zeaxanthin, may help
protect individuals from certain types of cancer. Another
carotenoid that has been identified for its health benefits
is lycopene, a red carotenoid found in tomatoes and berries.
How do
carotenoids help to maintain health?
Carotenoids act as antioxidants that protect healthy cells
from free radical damage. Free radicals are unstable
chemicals formed in the body during metabolism and from
exposure to environmental sources, such as pollution and
cigarette smoke. When there is an excessive number of free
radicals in the body, they can attack healthy cells and can
contribute to a number. of degenerative diseases, such as
cancer. Fortunately, antioxidants quench free radicals
before they have a chance to attack healthy cells.
As
antioxidants, carotenoids have been shown in the majority of
studies
to lower the risk for certain cancers, such as lung,
stomach, cervix, breast, bladder and oral cancers. Other
health benefits include protection against heart disease,
cataracts and age-related macular degeneration. In addition
to their antioxidant properties, it’s believed that
carotenoids reduce cancer risk early on by their ability to
enhance communication between premalignant cells and normal
cells. The presence of carotenoids appears to result in
normal cells sending growth-regulating signals to
premalignant cells.
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