Eyes, unlike wine, don’t get better with age, but they might be able to clue us in to another characteristic of growing old: memory loss. New research from the University of California at San Francisco found that people with even a little eye damage due to vascular disease have a higher risk for developing memory and thinking problems.

The key to this visual vexation is blood vessels, say scientists. If the blood vessels in the retina are damaged, it could mean blood vessels in the brain aren’t fully functioning either.

The study involved more than 500 older women who underwent periodic mental testing and brain scans. Compared with women who had no blood vessel damage in their eyes, those with impaired retinas also had more blood vessel damage in their brains and scored lower on memory and thinking tests.

Other blood pressure problems such as diabetes have also been related to a higher risk for memory and thinking troubles. Since eyes could be the first sign of trouble, clinicians may start looking for sign of dementia there.

To help avoid the problem altogether, look to basic nutrition to keep both your eyes and brain in the clear. Nutrients like omega-three fatty acids, found in fish and nuts, and lutein, found in leafy green vegetables, can ward off eye problems. Zinc and vitamins C and E also help maintain healthy eyes. Citrus, eggs and beans have been shown to protect peepers, too. Sport shades in the sun and give your eyes a break from staring at a computer screen every 20 minutes.

And to safeguard sight at the source, follow a heart-healthy diet to preserve blood vessels. Avoid smoking to ensure healthy blood flow and make sure to get enough aerobic exercise. The benefits of a well-balanced diet and active lifestyle are twofold: both your brain and your eyes will be better for it.