Could what patients eat influence their glaucoma risk? A large population-based analysis from The Maastricht Study suggests that adherence to national dietary guidelines may be associated with a lower prevalence of glaucoma – independent of intraocular pressure (IOP).
The cross-sectional study, led by Yu and colleagues at Maastricht University Medical Centre, The Netherlands, analyzed 5,729 adults aged 40–75 years. Diet quality was assessed using the Dutch Healthy Diet (DHD) Index, a comprehensive score reflecting adherence to national dietary recommendations, including higher intake of vegetables, fruits, whole grains, and fish, and lower consumption of processed foods. Participants also underwent detailed ophthalmic assessment, including visual field testing and IOP measurement.
The findings were striking: for every 10-point increase in DHD score, the odds of glaucoma were found to be 12.5% lower. Individuals in the highest DHD adherence tertile had a 38% lower likelihood of glaucoma compared with those in the lowest tertile.
Higher diet quality was also associated with slightly lower IOP. Each 10-point increase in DHD score corresponded to a reduction of approximately 0.17 mmHg. However, this effect size is small and unlikely to be clinically meaningful on its own.
Crucially, adjusting for IOP had minimal impact on the diet–glaucoma association. As indicated in the study, an estimated 7.4% of the association was explained via IOP, suggesting that other mechanisms are at play.
This aligns with the growing recognition that glaucoma is not purely an IOP-driven disease. Neurodegenerative, vascular, and metabolic pathways are increasingly implicated – and diet may intersect with all three.
Unlike many previous studies focusing on individual nutrients and their benefits, the study takes a broader view of dietary patterns, an approach that is perhaps better suited to capturing the cumulative and synergistic effects of nutrition on oxidative stress, inflammation, and vascular function.
The DHD Index itself reflects a largely plant-based dietary pattern, with moderate fish intake and reduced processed foods. The authors note that a 10-point improvement represents relatively modest, achievable dietary changes for patients – such as increasing vegetable consumption or reducing sugary drinks.
Overall, the study reinforces the idea that lifestyle factors could play an important role in glaucoma risk, even if the mechanisms are not yet fully understood. While dietary advice cannot replace established treatments, it may form part of a broader strategy for ocular and systemic health.
The findings add to a growing body of evidence linking diet quality to neurodegenerative diseases – and position glaucoma within that wider context. Future studies will need to explore whether targeted dietary interventions can meaningfully alter clinical outcomes.
For now, the message is nuanced but encouraging: a healthier diet may not just benefit the heart and brain – it could also play a role in protecting the optic nerve.
