Grape consumption might slow or help prevent the onset of age-related macular degeneration (AMD), a debilitating condition that affect millions of elderly people worldwide, a new study finds.
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 researchers found that 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," Silvia Finnemann, the principal investigator from Fordham University in New York, said.
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," she said.
Age-related macular degeneration is a progressive eye condition, leading to the deterioration of the centre 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.
This study showed that adding grapes to the diet prevented blindness in mice by significantly decreasing the build-up of lipofuscin and preventing the oxidative damage to the RPE, thus ensuring optimal functioning of this critical part of the retina.
"Preserving eye health is a key concern as we age and this study shows that grapes may play a critical role in achieving this," Kathleen Nave, president of the California Table Grape Commission, said.
"This is good news for consumers of all ages who enjoy grapes, and adds to the growing body of evidence that grapes offer an array of health benefits," Nave added.
The study has been published in Free Radical Biology and Medicine.