Vitamin Supplementation Reduces Glaucoma Risk in People With Raised Eye Pressure

How Nicotinamide Cuts Glaucoma Risk in Real-World Data

Patients with elevated intraocular pressure who take nicotinamide face significantly lower odds of developing primary open-angle glaucoma, according to a retrospective evaluation. Led by Jawad Muayad, MD, researchers examined electronic medical records spanning March 2006 to March 2026 across a research network of 67 U.S. healthcare companies. By tracking patients diagnosed with ocular hypertension who had not yet developed glaucoma or undergone laser surgery, investigators deployed propensity score matching to establish two balanced cohorts of 1,460 individuals each.

Over a mean follow-up period of 3.7 years, just 3.5% of the exposure group developed a formal primary open-angle glaucoma diagnosis, compared with 9.0% in the control group. That outcome translates to a hazard ratio of 0.34 and a relative risk reduction of 66%. The analysis also demonstrated that vitamin B3 supplementation was associated with a 43% lower risk of requiring prescription eye drops and a 62% reduction in the likelihood of needing laser trabeculoplasty surgery.

Safety Warnings and the Debate Over High Doses

Despite promising epidemiological data, major ophthalmological organizations urge caution regarding unsupervised supplementation. In March 2025, the American Academy of Ophthalmology and the American Glaucoma Society released a joint statement warning that taking high doses of nicotinamide can induce severe adverse health events, including liver damage.

The joint statement notes that while typical dosages range between 500 milligrams and 1,500 milligrams per day, ongoing clinical trials test amounts reaching 3 grams daily. Excess intake carries risks of gastrointestinal distress, fatigue, dizziness, headaches, blood disorders, elevated blood sugar, and liver toxicity.

Benjamin Bert, MD, a board-certified ophthalmologist at MemorialCare Orange Coast Medical Center in Fountain Valley, California, who was not involved in the study, emphasizes that patients should consult their physicians before altering their regimens. Because supplements are not regulated in the same way prescription medications are, individual oversight remains essential to monitor liver function and avoid adverse interactions with existing medications.

Cellular Mechanisms and Broader Metabolic Research

The epidemiological findings connect directly to years of laboratory research investigating cellular energy inside the eye. Simon John, a glaucoma researcher at Columbia University who serves as the Robert L. Burch III Professor of Ophthalmic Sciences, previously observed that mitochondrial dysfunction in retinal ganglion cells marks one of the earliest changes in animal models before visible retinal damage occurs. As mice age, levels of NAD—a molecule critical for mitochondrial health—decline, leaving neurons vulnerable to elevated intraocular pressure.

Complementary laboratory studies reinforce the metabolic approach.

Clinical Implications and Ongoing Trials

Glaucoma affects an estimated 95 million people globally. Because current treatments rely primarily on lowering eye pressure to slow damage rather than reversing lost vision, researchers are actively pursuing adjunctive therapies.

The authors of the JAMA Ophthalmology study suggest that nicotinamide could serve as a valuable complementary strategy to standard therapy, potentially delaying disease onset and reducing intervention burdens. Clinical trials are already underway to evaluate these metabolic interventions further.