New studies show they may predict disease risk.

Wouldn’t it be great if heart attacks came with a five-minute warning? Great news: your body has a built-in wellness indicator that just might save your life.

“[The eye is] the only place in the body where you can see a bare nerve, artery, and vein without surgery,” says Andrew Iwach, MD, Associate Clinical Professor of Ophthalmology at U.C. San Francisco, “The disease processes we see occurring in the eye are probably occurring in the rest of the body.”  

The interconnectedness of all the body’s systems is key to understanding our health and predicting our potential for chronic disease.  According to Daniel Gold, MD, author of The Eye in Systemic Disease, we have but one circulatory, nervous, and lymphatic system that services our entire body.

Doctors used to examine the eyes as part of a regular physical, but that practice has become uncommon. Getting an eye exam is easy and inexpensive—50 million Americans get one annually—but your eye doctor might choose to stick to her own specialty, hesitating to mention the overall health implications of any eye disease she discovers. 

An NIH study examining the role of vitamins in slowing macular degeneration found that  subjects with eye diseases had a higher instance of heart disease—and a much higher rate of mortality—than those with healthy eyes. For example, those in the study with wet macular degeneration and those having cataract surgery were 4 times and 2.5 times, respectively, more likely to die of heart disease than disease-free people the same age. More than six landmark studies show that certain eye diseases precede whole body disease and predict early mortality. 

So if you get suspect news from the eye doctor, head to the doctor-doctor for some full-body advice. Consider a diagnosis of cataract, glaucoma or retinal disease a prescription for adopting healthier habits—a chance to change the course of your own health.