A daily supplement of lutein in combination with vitamin A may slow vision loss associated with retinitis pigmentosa, according to the results of a randomized, controlled, double-blind trial.
Writing in the Archives of Ophthalmology, American scientists report
that a daily supplement containing 12 milligrams of lutein in
combination with 15,000 International Units of vitamin A (retinyl
palmitate) was associated with a preservation of mid-peripheral vision.
Rentinitis pigmentosa is a group of inherited eye diseases that affect
the retina. It causes the degeneration of photoreceptor cells in the
retina, bringing progressive vision loss to about one in 4,000 people
worldwide. Previous studies had found that taking vitamin A slows the
decline in retinal function and vision loss.
The new data indicates that 40 year olds with the condition who take the
vitamin A plus lutein combination would not be expected to lose their
mid-peripheral field until the age of 61, which would represent a
significant improvement compared with only 51 in people not taking
supplements of the carotenoid.
Lutein, a nutrient found in various foods including green leafy
vegetables and egg yolk, has a ten-year history in the dietary
supplement market as a nutrient to reduce the risk of age related
macular degeneration (ADM). It is often used in combination with
zeaxanthin.
Study details .- Led by Eliot Berson, MD, from the
Massachusetts Eye and Ear Infirmary, the researchers recruited 225
non-smoking people with retinitis pigmentosa aged between 18 and 60. The
participants were randomly assigned to receive vitamin A only (15,000
IU, retinyl palmitate) or vitamin A plus lutein (12 mg per day) for four
years.
While no significant effect was observed for the overall decline in
vision between the two groups, a significant reduction in the rate of
vision loss in the mid-peripheral region was observed.
According to the researchers, the average level of mid-peripheral
sensitivity for a patient aged 40 years is 375 dB. People taking the
lutein supplements lost on average 27 dB per year, while the other group
lost 34 dB per year, noted the researchers.
Safety .- No toxicity concerns were recorded during
the study, and the researchers noted that only non-smokers took part in
their study. Berson and his co-workers stated that there has been
concern for smokers taking long-term lutein supplementation.
“Follow-up of patients taking lutein and vitamin A with an oily fish
diet for at least 10 years would be needed to confirm these estimates
with respect to preserving midperipheral visual field,” concluded the
researchers.
Category: Productos
Source: Nutraingredients.com