http://www.luteininfo.com/
Introduction
Lutein (pronounced LOO-teen) is a carotenoid, meaning a natural colorant or pigment, found in dark green leafy vegetables such as spinach, plus various fruits and corn. Egg yolks are also sources of lutein.
Lutein provides nutritional support to our eyes and skin – the only organs of the body directly exposed to the outside environment. Lutein has been linked to promoting healthy eyes through reducing the risk of macular degeneration.** Other studies suggest that a mixture of nutrients, including lutein, may provide supplemental antioxidant capacity to the skin, helping counteract free radical damage.1
Why is lutein important in our diet? Simply put, lutein is an antioxidant that appears to quench or reduce harmful free radicals in various parts of the body.** Free radicals can play a role in a variety of chronic diseases.
Lutein also filters the high-energy, blue wavelengths of light from the visible-light spectrum by as much as 90%.2 Blue light, in both indoor lighting and sunlight, is believed to induce oxidative stress and possible free-radical damage in human organs exposed to light, such as the eyes and skin. Blue light is not the same as the commonly known ultraviolet A and ultraviolet B wavelengths of the invisible spectrum.
How much lutein do we need? Research suggests a minimum of 6-10 mg per day of lutein from dark green leafy vegetables and other sources is necessary to realize lutein’s health benefits. Even if you eat a balanced diet, you’d need a large bowl of fresh spinach to get about 6 mg of lutein. Most Americans just don’t consume enough foods rich in lutein. Lutein is widely available in a variety of nutritional supplements and fortified foods and beverages for people wanting to supplement their dietary intake of lutein, making their diet even better for their eyes and skin.
The LIB is also not aware of any adverse health reports from interactions between lutein and medications. However, the surest way to learn about possible interactions between your medication and any supplements is to consult your doctor before beginning such a regimen. The same is true for lutein.
We hope you find this site useful in learning much more about this amazing molecule with big health benefits…LUTEIN!
The lutein molecule
Lutein provides nutritional support to our eyes and skin – the only organs of the body directly exposed to the outside environment. Lutein has been linked to promoting healthy eyes through reducing the risk of macular degeneration.** Other studies suggest that a mixture of nutrients, including lutein, may provide supplemental antioxidant capacity to the skin, helping counteract free radical damage.1
Why is lutein important in our diet? Simply put, lutein is an antioxidant that appears to quench or reduce harmful free radicals in various parts of the body.** Free radicals can play a role in a variety of chronic diseases.
Lutein also filters the high-energy, blue wavelengths of light from the visible-light spectrum by as much as 90%.2 Blue light, in both indoor lighting and sunlight, is believed to induce oxidative stress and possible free-radical damage in human organs exposed to light, such as the eyes and skin. Blue light is not the same as the commonly known ultraviolet A and ultraviolet B wavelengths of the invisible spectrum.
How much lutein do we need? Research suggests a minimum of 6-10 mg per day of lutein from dark green leafy vegetables and other sources is necessary to realize lutein’s health benefits. Even if you eat a balanced diet, you’d need a large bowl of fresh spinach to get about 6 mg of lutein. Most Americans just don’t consume enough foods rich in lutein. Lutein is widely available in a variety of nutritional supplements and fortified foods and beverages for people wanting to supplement their dietary intake of lutein, making their diet even better for their eyes and skin.
The LIB is also not aware of any adverse health reports from interactions between lutein and medications. However, the surest way to learn about possible interactions between your medication and any supplements is to consult your doctor before beginning such a regimen. The same is true for lutein.
We hope you find this site useful in learning much more about this amazing molecule with big health benefits…LUTEIN!
The lutein molecule
http://en.wikipedia.org/wiki/Lutein
Lutein from Latin luteus meaning "yellow") is a xanthophyll and one of 600 known naturally occurring carotenoids.
Found in green leafy vegetables such as spinach and kale, lutein is employed by organisms as an antioxidant and for blue light absorption. Lutein is also found in egg yolks, animal fats, and the retina (zeaxanthin predominates at the macula lutea while lutein predominates elsewhere in the retina).[3]
The principal natural stereoisomer of lutein is (3R,3′R,6′R)-beta,epsilon-carotene-3,3′-diol. Lutein is a lipophilic molecule and is generally insoluble in water. The presence of the long chromophore of conjugated double bonds (polyene chain) provides the distinctive light-absorbing properties. The polyene chain is susceptible to oxidative degradation by light or heat and is chemically unstable in acids.
Lutein is present in plants as fatty-acid esters, with one or two fatty acids bound to the two hydroxyl-groups. For this reason, saponification (de-esterfication) of lutein esters to yield free lutein may yield lutein in any ratio from 1:1 to 1:2 molar ratio with the saponifying fatty acid.
Lutein is isomeric with zeaxanthin, differing only in the placement of one double bond.
[edit] As a pigment
This xanthophyll, like its sister compound zeaxanthin, has primarily been used as a natural colorant due to its orange-red color. Lutein absorbs blue light and therefore appears yellow at low concentrations and orange-red at high concentrations.Lutein was traditionally used in chicken feed to provide the yellow color of broiler chicken skin. Polled consumers viewed yellow chicken skin more favorably than white chicken skin. Such lutein fortification also results in a darker yellow egg yolk. Today the coloring of the egg yolk has become the primary reason for feed fortification. Lutein is not used as a colorant in other foods due to its limited stability, especially in the presence of other dyes.
[edit] Role in human eyes
Lutein was found to be concentrated in the macula, a small area of the retina responsible for central vision. The hypothesis for the natural concentration is that lutein helps keep the eyes safe from oxidative stress and the high-energy photons of blue light. Various research studies have shown that a direct relationship exists between lutein intake and pigmentation in the eye.[4][5][6][7][8][9][10]Lutein may play a role in Haidinger's brush, an entoptic phenomenon that allows humans to detect polarized light.
[edit] Macular Degeneration
Several studies show that an increase in macula pigmentation decreases the risk for eye diseases such as age-related macular degeneration (AMD).[11][12][13] The only randomized clinical trial to demonstrate a benefit for lutein in Macular Degeneration was a small study, in which the authors concluded that visual function is improved with lutein alone or lutein together with other nutrients and also that more study was needed .[12]There is epidemiological evidence of a relationship between low plasma concentrations of lutein and zeaxanthin, and an increased risk of developing age-related macular degeneration (AMD). Some studies support the view that supplemental lutein and/or zeaxanthin help protect against AMD.[14]
In 2007, in a 6-year study, John Paul SanGiovanni of the National Eye Institute, Maryland found that lutein and zeaxanthin (nutrients in eggs, spinach and other green vegetables) protect against blindness (macular degeneration), affecting 1.2 million Americans, mostly after age 65. Lutein and zeaxanthin reduce the risk of AMD.[14]
[edit] Cataracts
There is also epidemiological evidence that increasing lutein and zeaxanthin intake lowers the risk of cataract development.[14][15] Consumption of more than 2.4 mg of lutein/zeaxanthin daily from foods and supplements was significantly correlated with reduced incidence of nuclear lens opacities, as revealed from data collected during a 13- to 15-year period in the Nutrition and Vision Project (NVP).[16][edit] Photophobia(Light Sensitivity)
A study by Stringham and Hammond, published in the Jan-Feb issue of Journal of Food Science, discusses the improvement in visual performance and decrease in light sensitivity (glare) in subjects taking 10 mg Lutein and 2 mg Zeaxanthin per day.[17][edit] In nutrition
Lutein is a natural part of human diet when fruits and vegetables are consumed. For individuals lacking sufficient lutein intake, lutein-fortified foods are available, or in the case of elderly people with a poorly absorbing digestive system, a sublingual spray is available. As early as 1996, lutein has been incorporated into dietary supplements. While no recommended daily allowance currently exists for lutein as for other nutrients, positive effects have been seen at dietary intake levels of 6–10 mg/day.[18] The only definitive side effect of excess lutein consumption is bronzing of the skin (carotenodermia).The functional difference between lutein (free form) and lutein esters is not entirely known. It is suggested that the bioavailability is lower for lutein esters, but much debate continues.
As a food additive, lutein has the E number E161b and is extracted from the petals of marigold (Tagetes erecta).[19]
Some foods are considered good sources of the nutrients:[20][14][21]
| Product | Lutein/zeaxanthin (micrograms per hundred grams) |
|---|---|
| kale (cooked) | 18246 |
| turnip greens (raw) | 12825 |
| spinach (raw) | 12198 |
| spinach (cooked) | 11308 |
| turnip greens (raw) | 8440 |
| collard greens (cooked) | 7694 |
| gardenpeas | 2593 |
| romaine lettuce | 2312 |
| zucchini | 2125 |
| Brussels sprouts | 1590 |
| Pistachio nuts | 1205 |
| broccoli | 1121 |
| Maize/corn | 644 |
| egg | 353 |
| carrot | 256 |
| kiwifruit | 122 |
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