Lutein is an antioxidant found in plants. Like beta-carotene, it is a
carotenoid—a micronutrient responsible for the bright
colors of fruits and vegetables. Lutein is found in dark green leafy vegetables,
egg yolks, and red or yellow vegetables and fruits. Lutein has received some
attention for its apparent ability to help people with certain eye conditions.
Most of the attention has focused on macular degeneration, although recently
it's also been suggested that lutein supplements can improve vision in people
who have retinitis pigmentosa and/or related retinal degeneration.
A 1994 study looked at the relationship between dietary intake of carotenoids
and certain vitamins (A, C, and E) and the risk of age-related macular
degeneration, the leading cause of irreversible blindness among adults. The
researchers found that the more carotenoids in the diet, the lower the risk for
age-related macular degeneration. In particular, lutein and another carotenoid,
zeaxanthin, were most strongly associated with a reduced risk for age-related
macular degeneration. The authors of this study concluded that increasing
consumption of foods rich in certain carotenoids, in particular those found in
dark green, leafy vegetables, may decrease the risk of developing age-related
macular degeneration.
A more recent study looked at the relationship between lutein supplements and
other eye conditions that are characterized by deteriorating retina. For about 6
months, 16 people (recruited through the Internet) took 20 to 40 mg a day of
lutein. Lutein supplementation improved visual sharpness and increased the
central visual-field area (particularly when combined with vitamin A and/or
beta-carotene supplements). However, this study design does not stand up to
rigorous scientific standards. The investigators themselves suggest that larger,
placebo-controlled studies are needed to confirm and further investigate these
findings.
Although more research is needed, lutein supplementation (6 to 40 mg a day)
does appear promising, particularly for macular degeneration. Since some
supplements should not be taken if you have certain medical conditions or are
taking particular prescription medications, be sure to talk with your physician
or pharmacist to best determine which herbal or nutritional supplements are for
you.
