Ruth Martinez noticed her eye pressure was high during a routine checkup. The 58-year-old from Ohio had no symptoms, no blurry vision, nothing to worry about on the surface. But doctors warned her she was at risk for glaucoma — a disease that steals sight so quietly, many people don't know they have it until it's too late. Now, new research suggests something as simple as a vitamin pill might give her, and millions of others like her, a fighting chance.
A major study published in JAMA Ophthalmology found that people taking nicotinamide — a form of vitamin B3 — had a 66% lower risk of developing glaucoma compared to those who didn't take it. Researchers analyzed anonymous health records from 67 healthcare organizations across the United States over 20 years. They focused on 2,920 patients who already had high eye pressure but hadn't yet developed the disease. Half were taking nicotinamide supplements, and half weren't.
Over about 3.7 years of follow-up, only 3.5% of nicotinamide users went on to develop glaucoma. That compared to 9% of people who didn't take the supplement. The difference was striking.
The researchers used a careful method called propensity score matching — basically pairing each person taking the vitamin with a similar person of the same age, sex, and medical history who wasn't taking it. This helped make the comparison as fair as possible. They then tracked both groups to see who developed glaucoma, who needed prescription eye drops, and who required laser treatment.
People not taking nicotinamide were more than twice as likely to need laser therapy to manage their condition. And 21.2% of non-users needed prescription eye drops to lower their eye pressure, compared to just 13.6% of those taking the supplement.
So why might this vitamin help? Scientists now understand that glaucoma is partly a metabolic disease — meaning it has to do with how cells produce energy. As people age, levels of a molecule called NAD+ naturally drop. NAD+ helps cells in the retina repair damage and stay energized. When it falls, eye cells become vulnerable. Nicotinamide appears to help replenish NAD+, supporting repair and blood flow in the eyes.
The protective effect even showed up in patients who only started taking nicotinamide after their high eye pressure was already diagnosed — suggesting it might help slow disease progression, not just prevent it.
Of course, scientists are quick to point out that this was an observational study, meaning it can't definitively prove the vitamin caused the benefit. Larger clinical trials are still needed to confirm the effects, figure out the safest and most effective dose, and understand the long-term impact.
Still, for the millions of Americans living with high eye pressure — watching and waiting to see if glaucoma will take their sight — this research offers real hope that something simple might be worth asking your doctor about.