Chlorogenic acid (CGA), a powerful polyphenol found in coffee, may prevent retinal damage caused by glaucoma, diabetic retinopathy and AMD, according to food science researchers at Cornell University._¹ Previous studies have indicated that regular coffee consumption reduces patients’ risk of other degenerative conditions, such as Parkinson’s disease._² The Cornell researchers believe that these antioxidative benefits may be due, in part, to the neuroprotective effects of CGA.

The study, published in the December 20, 2013 online edition of the Journal of Agricultural and Food Chemistry, evaluated whether a synthetically prepared CGA solution or a crude coffee extract could prevent retinal degeneration induced by nitric oxide exposure in a mouse model. The researchers determined that mice treated with either the CGA solution or the coffee extract experienced a lower incidence of retinal ganglion cell apoptosis than the controls.

With these results in mind, the researchers aim to determine just how much java is required to yield these protective benefits. “We are now in the process of finding out how much of the active compound can pass through the blood-retinal barrier using a mouse model,” says senior author Chang Y. Lee, PhD, professor of food science at Cornell. Further study will eventually confirm how much chlorogenic acid and coffee must be consumed and subsequently absorbed to reach the retinal tissues successfully, he adds.

But one important question remains: Can coffee consumption actually prevent retinal degeneration in humans? “Since most bioactive phytochemicals, such as chlorogenic acid in coffee and catechins in green tea, undergo extensive transformation in the human digestive system, we are [still evaluating] the bioactivities of CGA metabolites,” says Dr. Lee. “In the meantime, I think that regular consumption of coffee may reduce retinal degeneration, along with cognitive declines associated with aging.”
 
1. Jang H, Ahn HR, Jo H, et al. Chlorogenic acid and coffee prevent hypoxia-induced retinal degeneration. J Agric Food Chem. 2013 Dec 20. [Epub ahead of print]
2. Ross GW, Abbott RD, Petrovitch H, et al. Association of coffee and caffeine intake with the risk of Parkinson disease. JAMA. 2000 May 24-31;283(20):2674-9.