Grapes may help prevent age-related blindness

Can eating grapes slow or help prevent the onset of age-related macular degeneration (AMD), a debilitating condition affecting millions of elderly people worldwide? Results from a new study published in Free Radical Biology and Medicine suggest this might be the case. The antioxidant actions of grapes are believed to be responsible for these protective effects.

The study compared the impact of an antioxidant-rich diet on vision using mice prone to developing retinal damage in old age in much the same way as humans do. Mice either received a grape-enriched diet, a diet with added lutein, or a normal diet.

The result? Grapes proved to offer dramatic protection: the grape-enriched diet protected against oxidative damage of the retina and prevented blindness in those mice consuming grapes. While lutein was also effective, grapes were found to offer significantly more protection.

"The protective effect of the grapes in this study was remarkable, offering a benefit for vision at old age even if grapes were consumed only at young age," said principal investigator Silvia Finnemann, PhD, Department of Biological Sciences, Fordham University in New York.

Dr. Finnemann noted that results from her study suggest that age-related vision loss is a result of cumulative, oxidative damage over time. "A lifelong diet enriched in natural antioxidants, such as those in grapes, appears to be directly beneficial for RPE and retinal health and function."

Age-related macular degeneration (AMD) is the leading cause of blindness among the elderly, and it affects more than 10 million Americans age 55 and older, according to the American Macular Degeneration Foundation. A recent study published in Free Radical Biology and Medicine looked to see if an antioxidant-rich diet would help sufferers ward of the condition for longer, and the results were surprising.

To test this, researchers studied mice because they are prone to developing retinal damage in old age in a similar fashion to humans. The mice were broken up into three groups, one ate a diet rich in grapes, a second group ate a diet with added lutein - a pigment found in plants known to support eye health, and the third group consumed a normal diet.

From the data, scientists found that the mice who ate the grapes were the most protected against the effects of AMD. The grapes worked to shield the mice's eyes against oxidative damage of the retina and prevented blindness as well. The mice who ate a diet with added lutein also had benefits, though the grapes were far superior in providing overall protection.

Age-related macular degeneration is a progressive eye condition, leading to the deterioration of the center of the retina, called the macula. It is the leading cause of blindness in the elderly. Aging of the retina is associated with increased levels of oxidative damage, and oxidative stress is thought to play a pivotal role in the development of AMD.