|
Lutein is a member of the carotenoid family. Carotenoids are
naturally occurring fat-soluble pigments found in a few plants, such
as algae and certain plant bacteria. They serve as accessory
light-gathering pigments and are used protect against the toxic
effects of ultra-violet radiation and oxidation. Lutein appears to
have the ability to protect humans against phototoxic damage as
well. Lutein is found in the macula of the human retina as well as
in the human crystalline lens and is thought to play a role in
protection against age-related macular degeneration (ARMD) and
age-related cataract formation and may protect against certain forms
of cancer.
Food sources of lutein include corn, egg yolks,
and green vegetables and fruits such as broccoli, green beans, green
peas, brussels sprouts, cabbage, kale, collard greens, spinach,
lettuce, kiwi, and honeydew. Lutein is also found in herbs such as
nettles, algae, and the petals of many yellow flowers. Many of the
marketed lutein nutritional supplements contain lutein esters which
are derived from the dried petals of marigold
flowers.
Dosage and
Administration
Lutein is available as a
non-esterified and esterified forms and as single ingredient or in
combination with other nutritional supplements. Many times
zeaxanthin (a similar carotenoid with similar effects) is also found
along side lutein in smaller concentrations; however supplements
that deliver higher amounts of zeaxanthin are being
developed.
The optimal dosage for lutein supplementation is
unknown. It has been suggested that dietary intake of lutein of 6 to
12 milligrams per day has been associated with a decreased risk of
age-related macular degeneration.
|
