A long-term diet low in carbohydrates and rich in plant-based fats and proteins may lower the risk of glaucoma, researchers say.

Glaucoma is a leading cause of blindness due to damage to the optic nerve from abnormally high pressure in the eye, according to the Mayo Clinic. A healthy optic nerve is important for quality vision.

Research from the New York Eye and Ear Infirmary of Mount Sinai will be published in the July 22 print issue of Eye-Nature.

Specifically, they found that a diet higher in plant-based fat and protein and low in carbohydrates can cut the risk of developing primary open angle glaucoma (POAG), or a common subtype of glaucoma, with early paracentral visual loss by 20 percent.


“This dietary pattern has already been shown to have favorable results for epilepsy and showed some promising results for Parkinson’s and Alzheimer’s diseases,” said Dr. Louis R. Pasquale, co-corresponding author and deputy chair for ophthalmology research for the Mount Sinai Health System.

“It’s important to note that a low-carbohydrate diet won’t stop glaucoma progression if you already have it, but it may be a means to preventing glaucoma in high-risk groups. If more patients in these high-risk categories—including those with a family history of glaucoma—adhered to this diet, there might be fewer cases of vision loss,” Pasquale added.

The optic nerve relays visual information and connects the back of the eye and retina to the brain. It has a high concentration of mitochondria, which supplies energy to the cell. The researchers wanted to know if substituting protein and fat for carbohydrates in the diet would improve mitochondrial activity and maintain optic nerve function.

Researchers followed more than 185,000 participants of three cohorts from 1976 to 2017, who filled out food frequency questionnaires every two to four years, along with health related questions. The team examined carbohydrate intake across animal-based and plant-based fats and proteins, as well as those coming from any source.

Overall, the findings suggest that vegetable sources may be more beneficial than animal sources for a low-carbohydrate diet in reducing the risk of a certain glaucoma subtype.

“This was an observational study and not a clinical trial, so more work is needed as this is the first study looking at this dietary pattern in relation to POAG,” Pasquale said. “The next step is to use artificial intelligence to objectively quantify paracentral visual loss in our glaucoma cases and repeat the analysis.”

“It’s also important to identify patients who have a genetic makeup of primary open angle glaucoma who may benefit from a low-carbohydrate diet. This dietary pattern may be protective only in people with a certain genetic makeup,” Pasquale added.