Useful Information On Lutein
Lutein is a yellow pigment in the chemical family of carotenoids and produced by
vegetables, marigold flowers, alfalfa and to a lesser degree in many other plants. The
original medical association of Lutein was as an isolate from the corpus luteum, a part of
the ovaries, and hence its name (Latin for egg yolk), but an important medical aspect is
its presence in the macula of the eye where it is strongly implicated in maintaining eye
health. Humans do not synthesize lutein and depend entirely on dietary sources such as
vegetables or supplement lutein pills.
Carotenoids are a subclass of phytonutruients which are prominent in fruits and
vegetables and have antioxidant as well as other biological activities that may promote
health. Lutein and lycopene are among the most abundant dietary carotenoids found in
fruits, vegetables and human serum.
Lutein and zeaxanthin also happen to be the main pigments in part of the eye called the
macula. Research shows that people with diets rich in lutein and zeaxanthin are at a lower
risk for degeneration of the macula, which is the leading cause of blindness in older
adults.
Lutein has in the past several years been the subject of many studies associating it
with risk reduction for failing eyesight due to Age-related Macular Degeneration or AMD,
and therefore has generated significant interest. A general conclusion from the
information available is that increased dietary intake of Lutein reduces the risk for
macular degeneration. Note that risk reduction does not imply a cure once macular
degeneration has started but reduction of risk implies prevention for some people, and
slowing or halting the progression of macular degeneration once it starts could be
realistic expectations as more studies are indicating.
A recent study relating lutein to macular degeneration by Stuart Richer, O.D. presented
at the Southern Council of Optomitrists 1999 annual meeting, indicated "improvements in
visual function in as little as three months. Often striking improvements in vision were
detected through follow-up tests, even when the patient did not report subjective vision
changes" in study subjects with the dry form of macular degeneration after a diet
supplemented with lutein rich foods. Since the study group apparently did not include
subjects with wet form macular degeneration it would not be scientifically prudent to
assume that both forms would have the same results. Yet assuming that the wet form would
not benefit may not be a prudent approach either, considering the relative ease and
inexpense of supplementing a diet with lutein rich foods or lutein pills.
Sufficient lutein of the quantity indicated for macular degeneration risk reduction can
be obtained from a proper diet, but considering that this requires daily attention to the
lutein content of specific food items not usually present in a diet and the disciplinary
persistence to maintain that attention, many people may not obtain the lutein required for
macular degeneration risk reduction solely from diet. Often people in the over 75 high
risk group reside in senior housing complexes where meals are supplied and the option to
select a lutein rich diet is not available.
The compounds lutein and zeaxanthin form the macular pigment (color)
found in the eye. High levels of these compounds in the eye are thought
to prevent age-related macular degeneration, a form of blindness. The
purpose of this study was to determine whether the amount of lutein and
zeaxanthin in the blood macular pigment in the eye could be raised by
increasing the intake of foods which contain lutein and zeaxanthin.
Over a 14-15 week period ten subjects added spinach to their usual
diets; 9 subjects also added corn; and 2 subjects were given only corn.
For those who ate the spinach supplemented diets, seven subjects had
increases in blood lutein and zeaxanthin levels and increases in
macular pigment eye levels. Two subjects showed increases in lutein and
zeaxanthin levels but no change in eye macular pigment levels. One
subject showed no changes in lutein, zeaxanthin or macular pigment
blood levels. For the 2 subjects given only corn, blood zeaxanthin and
eye macular pigment of one subject increased, while there was no change
in the blood nor the eye levels of the other subject. Macular pigment
increases were seen within 4 weeks for most, but not all, subjects and
remained high for at least several months after supplementation. It
appears that macular pigment can be increased by increasing intake of
foods containing lutein and zeaxanthin.
A true phytochemical heavyweight, leafy green kale contains lutein and zeaxanthin, two
carotenoids with powerful antioxidant properties. Lutein constitutes between 15 and 47 per
cent of the carotenoid content of dark green leafy vegetables.
Lutein acts as an antioxidant, protecting cells against the damaging effects of free
radicals. At one time researchers believed all antioxidants served the same purpose. Now
there is growing evidence that individual axtioxidants may be used by the body for
specific purposes. Researchers believe that lutein is deposited into areas of the body
most prone to free radical damage.
Carotenoids have numerous biological properties that may underpin a role for them as
chemopreventive agents. However, except for beta-carotene, little is known about how
dietary carotenoids are associated with common cancers, including colon cancer. The
objective of this study was to evaluate associations between dietary alpha-carotene,
beta-carotene, lycopene, lutein, zeaxanthin, and beta-cryptoxanthin and the risk of colon
cancer. Lutein was inversely associated with colon cancer in both men and women. The
greatest inverse association was observed among subjects in whom colon cancer was
diagnosed when they were young and among those with tumors located in the proximal segment
of the colon. The associations with other carotenoids were unremarkable.
CONCLUSION: The major dietary sources of lutein in subjects with
colon cancer and in control subjects were spinach, broccoli, lettuce,
tomatoes, oranges and orange juice, carrots, celery, and greens. These
data suggest that incorporating these foods into the diet may help
reduce the risk of developing colon cancer.
The consumption of fruits and vegetables has been associated with reduced risk of
several types of cancers. Carotenoids are abundant in these foods and have been proposed
as cancer protective compounds because of their antioxidant and provitamin A activities.
Lutein, an abundant carotenoid in many fruits and vegetables but without vitamin A
activity, has been shown to possess strong antioxidant capability in laboratory studies.
Results from the present study demonstrate that lutein and zeaxanthin, an isomer of lutein,
are partially oxidized in vivo to several metabolites. These observations confirm the
antioxidant activity of lutein in vivo which supports one of the proposed cancer
protective mechanisms of carotenoids. Results and conclusions from these studies will
benefit the diet and health community as well as policy makers.
This research addressed the question of how carotenoids might lower
the risk for certain chronic diseases by testing the antioxidant
activity of beta-carotene (BC) and lutein (lut). BC and lut are found
in all human blood in relatively high concentrations. The test model
was a human liver cell line, HEP-G2. The cells were exposed to several
conditions of potential injury due to "oxidative" stress. The results
support the concept that both BC and lut protect human cells against
damage. In some of the tests, the carotenoids were as effective as the
reference substance, vitamin E (alpha-tocopherol), which is recognized
as an effective cell protector (antioxidant). The results also
demonstrated that the protective effect of BC and lutein was not due to
being converted to vitamin A (VA) since lut (unlike BC) has no such
potential. Thus, this research involving human cells provides data
which supports the general hypothesis that BC and lut protect cells by
serving as antioxidants. These findings will benefit other scientists
working in the area. In addition, the results will add to our knowledge
which in the future may help prevent or delay chronic diseases in our
aging U.S. population as well as other individuals.
Lutein is a yellow pigment in the chemical family of carotenoids and produced by
vegetables, marigold flowers, alfalfa and to a lesser degree in many other plants. The
original medical association of Lutein was as an isolate from the corpus luteum, a part of
the ovaries, and hence its name (Latin for egg yolk), but an important medical aspect is
its presence in the macula of the eye where it is strongly implicated in maintaining eye
health. Humans do not synthesize lutein and depend entirely on dietary sources such as
vegetables or supplement lutein pills.
Carotenoids are a subclass of phytonutruients which are prominent in fruits and
vegetables and have antioxidant as well as other biological activities that may promote
health. Lutein and lycopene are among the most abundant dietary carotenoids found in
fruits, vegetables and human serum.
Lutein and zeaxanthin also happen to be the main pigments in part of the eye called the
macula. Research shows that people with diets rich in lutein and zeaxanthin are at a lower
risk for degeneration of the macula, which is the leading cause of blindness in older
adults.
Lutein has in the past several years been the subject of many studies associating it
with risk reduction for failing eyesight due to Age-related Macular Degeneration or AMD,
and therefore has generated significant interest. A general conclusion from the
information available is that increased dietary intake of Lutein reduces the risk for
macular degeneration. Note that risk reduction does not imply a cure once macular
degeneration has started but reduction of risk implies prevention for some people, and
slowing or halting the progression of macular degeneration once it starts could be
realistic expectations as more studies are indicating.
A recent study relating lutein to macular degeneration by Stuart Richer, O.D. presented
at the Southern Council of Optomitrists 1999 annual meeting, indicated "improvements in
visual function in as little as three months. Often striking improvements in vision were
detected through follow-up tests, even when the patient did not report subjective vision
changes" in study subjects with the dry form of macular degeneration after a diet
supplemented with lutein rich foods. Since the study group apparently did not include
subjects with wet form macular degeneration it would not be scientifically prudent to
assume that both forms would have the same results. Yet assuming that the wet form would
not benefit may not be a prudent approach either, considering the relative ease and
inexpense of supplementing a diet with lutein rich foods or lutein pills.
Sufficient lutein of the quantity indicated for macular degeneration risk reduction can
be obtained from a proper diet, but considering that this requires daily attention to the
lutein content of specific food items not usually present in a diet and the disciplinary
persistence to maintain that attention, many people may not obtain the lutein required for
macular degeneration risk reduction solely from diet. Often people in the over 75 high
risk group reside in senior housing complexes where meals are supplied and the option to
select a lutein rich diet is not available.
The compounds lutein and zeaxanthin form the macular pigment (color)
found in the eye. High levels of these compounds in the eye are thought
to prevent age-related macular degeneration, a form of blindness. The
purpose of this study was to determine whether the amount of lutein and
zeaxanthin in the blood macular pigment in the eye could be raised by
increasing the intake of foods which contain lutein and zeaxanthin.
Over a 14-15 week period ten subjects added spinach to their usual
diets; 9 subjects also added corn; and 2 subjects were given only corn.
For those who ate the spinach supplemented diets, seven subjects had
increases in blood lutein and zeaxanthin levels and increases in
macular pigment eye levels. Two subjects showed increases in lutein and
zeaxanthin levels but no change in eye macular pigment levels. One
subject showed no changes in lutein, zeaxanthin or macular pigment
blood levels. For the 2 subjects given only corn, blood zeaxanthin and
eye macular pigment of one subject increased, while there was no change
in the blood nor the eye levels of the other subject. Macular pigment
increases were seen within 4 weeks for most, but not all, subjects and
remained high for at least several months after supplementation. It
appears that macular pigment can be increased by increasing intake of
foods containing lutein and zeaxanthin.
A true phytochemical heavyweight, leafy green kale contains lutein and zeaxanthin, two
carotenoids with powerful antioxidant properties. Lutein constitutes between 15 and 47 per
cent of the carotenoid content of dark green leafy vegetables.
Lutein acts as an antioxidant, protecting cells against the damaging effects of free
radicals. At one time researchers believed all antioxidants served the same purpose. Now
there is growing evidence that individual axtioxidants may be used by the body for
specific purposes. Researchers believe that lutein is deposited into areas of the body
most prone to free radical damage.
Carotenoids have numerous biological properties that may underpin a role for them as
chemopreventive agents. However, except for beta-carotene, little is known about how
dietary carotenoids are associated with common cancers, including colon cancer. The
objective of this study was to evaluate associations between dietary alpha-carotene,
beta-carotene, lycopene, lutein, zeaxanthin, and beta-cryptoxanthin and the risk of colon
cancer. Lutein was inversely associated with colon cancer in both men and women. The
greatest inverse association was observed among subjects in whom colon cancer was
diagnosed when they were young and among those with tumors located in the proximal segment
of the colon. The associations with other carotenoids were unremarkable.
CONCLUSION: The major dietary sources of lutein in subjects with
colon cancer and in control subjects were spinach, broccoli, lettuce,
tomatoes, oranges and orange juice, carrots, celery, and greens. These
data suggest that incorporating these foods into the diet may help
reduce the risk of developing colon cancer.
The consumption of fruits and vegetables has been associated with reduced risk of
several types of cancers. Carotenoids are abundant in these foods and have been proposed
as cancer protective compounds because of their antioxidant and provitamin A activities.
Lutein, an abundant carotenoid in many fruits and vegetables but without vitamin A
activity, has been shown to possess strong antioxidant capability in laboratory studies.
Results from the present study demonstrate that lutein and zeaxanthin, an isomer of lutein,
are partially oxidized in vivo to several metabolites. These observations confirm the
antioxidant activity of lutein in vivo which supports one of the proposed cancer
protective mechanisms of carotenoids. Results and conclusions from these studies will
benefit the diet and health community as well as policy makers.
This research addressed the question of how carotenoids might lower
the risk for certain chronic diseases by testing the antioxidant
activity of beta-carotene (BC) and lutein (lut). BC and lut are found
in all human blood in relatively high concentrations. The test model
was a human liver cell line, HEP-G2. The cells were exposed to several
conditions of potential injury due to "oxidative" stress. The results
support the concept that both BC and lut protect human cells against
damage. In some of the tests, the carotenoids were as effective as the
reference substance, vitamin E (alpha-tocopherol), which is recognized
as an effective cell protector (antioxidant). The results also
demonstrated that the protective effect of BC and lutein was not due to
being converted to vitamin A (VA) since lut (unlike BC) has no such
potential. Thus, this research involving human cells provides data
which supports the general hypothesis that BC and lut protect cells by
serving as antioxidants. These findings will benefit other scientists
working in the area. In addition, the results will add to our knowledge
which in the future may help prevent or delay chronic diseases in our
aging U.S. population as well as other individuals.
- Dr. Stuart Richer. Dietary Modification With A Lutein-rich Food Reverses Armd Vision Loss, According To Optometric
- Hammond Billy R, Johnson Elizabeth J, Et Al. Dietary Modification Of Human Macular Pigment Density
- Fruits and vegetables that are sources for lutein and zeaxanthin: the macular pigment in human eyes
- Slattery
ML; Benson J; Curtin K; Ma KN; Schaeffer D; Potter JD. Carotenoids and
colon cancer. Am J Clin Nutr 2000 Feb;71(2):575-82 - Khachik
Frederick, Beecher Gary R, Smith Jr James C. Lutein, Lycopene, And
Their Oxidative Metabolites In Chemoprevention Of Cancer - Martin
Keith R, Failla Mark L, Smith Jr James C. Beta-carotene And Lutein
Protect The Plasma Membrane Of Hepg2 Human Liver Cells Against
Oxidant-induced Damage
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