Millions of people around the world are at risk of glaucoma, a disease that slowly damages the optic nerve and can eventually cause permanent blindness.
One of the challenges of glaucoma is that many people notice no symptoms until vision has already been lost. Doctors usually focus on lowering pressure inside the eye because high pressure greatly increases the risk of damage.
However, even with successful treatment, some patients continue to experience worsening vision. Scientists are therefore searching for new ways to protect the optic nerve itself.
A recent study published in JAMA Ophthalmology points to a possible new option: nicotinamide, a form of vitamin B3. Researchers found that people with high eye pressure who took nicotinamide appeared much less likely to develop primary open-angle glaucoma than similar patients who did not use the supplement.
The study was based on electronic medical records collected over twenty years from 67 healthcare organisations across the United States. Researchers identified nearly 3,000 adults with ocular hypertension who had not yet been diagnosed with glaucoma.
To ensure a fair comparison, every person taking nicotinamide was matched with someone of similar age, sex, health conditions and eye disease who was not taking the supplement.
Participants were followed for almost four years. During that time, only 3.5 percent of nicotinamide users developed glaucoma, compared with 9 percent of non-users. Overall, people taking the vitamin had about a 66 percent lower chance of developing the disease.
The researchers also looked at whether patients eventually needed stronger treatment. They found that fewer nicotinamide users required prescription eye drops to reduce eye pressure. They were also much less likely to undergo laser treatment, suggesting that the disease progressed more slowly.
Scientists believe these benefits may be linked to the way nicotinamide supports energy production inside retinal cells. As people age, levels of nicotinamide adenine dinucleotide naturally fall. This important molecule helps cells generate energy and repair damage.
Without enough of it, the optic nerve may become more vulnerable to stress caused by high eye pressure. By increasing the supply of this molecule, nicotinamide may help retinal cells survive for longer.
These findings add to growing evidence that glaucoma is not simply caused by pressure inside the eye. Changes in metabolism and cell energy may also play an important role. This broader understanding is encouraging researchers to explore treatments that protect nerve cells in addition to lowering eye pressure.
Despite the promising results, experts emphasise that nicotinamide is not yet a proven treatment for preventing glaucoma.
Because the study was observational, it cannot prove that the vitamin itself caused the lower risk. Randomised clinical trials are needed to confirm the findings and determine the most effective and safest dose before doctors can recommend routine use.
If you care about eye health, please read studies about how vitamin B may help fight vision loss, and MIND diet may reduce risk of vision loss disease.
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