Vitamin mix shows promise for protecting sight in glaucoma research

New research indicates that a blend of B vitamins and choline helped protect the optic nerve in animal models of glaucoma, pointing to a possible new way to help preserve vision. The findings suggest that improving eye metabolism could work alongside treatments that mainly lower eye pressure.

That is significant because glaucoma harms the nerve that carries visual signals from the eye to the brain. Although current treatments can slow the damage, some patients still lose sight, which makes other strategies for safeguarding vulnerable nerve cells an important research target.

The idea is appealing because it focuses on the cells’ underlying biology rather than pressure alone. Even so, the vitamin combination has not been proven as a treatment for patients, and the study does not show that it can restore vision already lost to glaucoma.

Researchers at Karolinska Institutet, working with international collaborators, reported the study in Cell Reports Medicine in 2025. They examined a network of vitamin-dependent chemical reactions in the retina and optic nerve through animal experiments and analysis of human data.

The work began with homocysteine, a compound involved in normal metabolism that can be elevated in glaucoma. The researchers wanted to know whether it directly caused damage or simply signaled that other important processes were disturbed.

Experiments showed only limited harmful effects from raising homocysteine, while the human data did not reveal a clear impact of higher blood levels on glaucoma progression. Genetic predisposition to higher homocysteine also showed no clear link with the glaucoma outcomes studied.

Attention then turned to the metabolic pathways themselves. The team found abnormalities in the transport, processing, or use of nutrients that support these reactions, suggesting that a higher marker may reflect a broader problem in retinal metabolism.

They next tested supplements containing vitamins B6, B9 and B12 together with choline. The combination protected nerve cells in experimental glaucoma, with stronger protection in a slower chronic model and more modest protection in an acute model involving raised eye pressure.

The effect was not explained by a reduction in eye pressure, which suggests a potentially complementary mechanism. Still, animal models only capture parts of human disease, so protection in these experiments cannot establish the correct dose, safety, or clinical benefit for patients.

Human diet analyses also failed to show a clear overall link between greater B-vitamin intake and better glaucoma-related outcomes. In its 2025 announcement, Karolinska Institutet said a clinical trial had started at S:t Eriks Eye Hospital to test the approach in patients.

Clinical testing is necessary because supplements can cause side effects and research doses cannot simply be copied into everyday use. People with glaucoma should continue their prescribed eye care; the study offers a promising path for added protection, but only patient data can show whether it leads to safer, lasting preservation of sight.

For broader related reading, please see articles about Too much vitamin B6 can be toxic. 3 symptoms to watch out for, and How vitamin supplementation may affect the dementia risk.

For more information, please see articles about All about vitamin C: why we need it and how to get it, and Do ‘health foods’ really help?.

Source: Karolinska Institutet.