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 also 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 retinal health and function."
AMD 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. Oxidative damage and oxidative stress are thought to play a pivotal role in the development of AMD.