Fruit, not supplements, may protect against age-related eye disease
age-related maculopathy (ARM), an eye disease that can cause
blindness, according to US scientists.
ARM, also referred to as age-related macular degeneration in the late stages, is the leading cause of vision loss among people 65 and older. There are no effective treatments for ARM so prevention of this eye disease is key to reducing the growing incidence.
However while a recent study found that supplementation with high-doses of vitamins C and E, beta-carotene and zinc delayed the progression of ARM, the new study shows no strong association between intake of vitamins or carotenoids either from food only or from food and supplements and ARM risk.
Similarly, no substantial associations were observed between vegetable intake and ARM.
The new findings, published in the June issue of The Archives of Ophthalmology (122:883-892), were based on the development of ARM among 77,562 women and 40,866 men participating in the Nurses' Health Study (women) and the Health Professionals Follow-up Study (men).
Eunyoung Cho from the Brigham and Women's Hospital, Boston, and colleagues examined the effect of antioxidant vitamins and carotenoids (compounds responsible for the red, yellow and orange pigments found in some fruits and vegetables) as well as fruits and vegetables on the participants, who were all at least 50 years old at the beginning of the study and free of ARM.
Women were followed for up to 18 years, and men were followed for up to 12 years, with both completing food consumption questionnaires regularly over the follow-up period. Participants also reported their vitamin and supplement use once every two years.
The researchers found that fruit consumption was inversely associated with risk of neovascular ARM, the form of the disease that frequently involves severe vision loss.
Participants who ate three or more servings per day of fruit had a 36 per cent lower risk of ARM compared to those who reported eating less than 1.5 servings per day.
But Cho's team said that none of the vegetable items appeared to be strongly related to either early or neovascular ARM risks, "except that carrot intake had a weak, non-significant inverse association with the neovascular form".
"None of the antioxidant vitamins and carotenoids was strongly related to either early or neovascular ARM risk, although many of them, including total carotenoids, had a suggestive inverse association with neovascular ARM risk," the researchers added.
The study conflicts with evidence to show that supplements of lutein, a carotenoid, can help both prevent age-related macular degeneration and may even be able to reverse some of the damage done by the disease.
