Health + Fitness | Research shows link between diet and glaucoma management

What a person eats may influence how glaucoma is managed, potentially affecting how much medication is needed to control the debilitating eye condition.

Health researcher Genesis Edokpa draws a link between diet and disease severity in his paper, Association Between Diet and Number of Prescribed Medications in Glaucoma Patients. The study was presented at the Ministry of Health and Wellness’ 16th Annual National Research Conference, held earlier this year at The Jamaica Pegasus hotel in New Kingston.

Edokpa, based at the Caribbean Institute for Health Research (CAIHR) at The University of the West Indies (UWI), Mona, noted that glaucoma — one of the leading causes of irreversible blindness worldwide — disproportionately affects Afro-Caribbean populations, who are six to eight times more likely to develop the disease than their Caucasian counterparts.

Glaucoma is characterised primarily by increased intraocular pressure, which damages the optic nerve over time and leads to irreversible vision loss.

In clinical practice, the aim is to reduce that pressure, typically through medicated eye drops or surgery. However, as Edokpa explains, there are up to six classes of glaucoma medications, and patients may require several at once when one proves insufficient.

“The number of medications used can serve as a proxy for how severe or difficult the disease is to control,” he pointed out.

This has prompted interest in whether lifestyle choices — particularly diet — might play a complementary role. While previous studies suggest certain foods may influence glaucoma risk, Edokpa highlights a gap: none had directly examined the relationship between dietary habits and the number of medications required to manage the condition.

To address this, he conducted a cross-sectional study involving 109 patients with primary open-angle glaucoma, the most common form of the disease. Participants were recruited from the University Hospital of the West Indies and a private ophthalmology practice in Kingston.

Using a detailed health and lifestyle questionnaire, the study assessed both prescribed medications and dietary intake over a three-month period. Foods were grouped into 10 categories, from cereals and starchy staples to vegetables, fruits, fish, and beverages such as coffee and tea. Participants reported frequency and portion sizes, allowing researchers to estimate average daily intake.

The analysis also accounted for factors such as age, sex, hypertension, diabetes, physical activity, and medication adherence, all of which could influence disease severity.

Initial findings showed little association between most food groups and medication use, with two notable exceptions: fish and vegetables. Higher consumption of both was significantly linked to fewer prescribed glaucoma medications.

Edokpa said the explanation likely lies in their biological properties. Fish — especially sardines, tuna, and mackerel — are rich in omega-3 fatty acids, which have been shown to reduce intraocular pressure. Vegetables, particularly leafy greens such as callaloo, pak choi, spinach, and kale, contain nitrates and antioxidant vitamins that support improved fluid outflow in the eye, also helping to lower pressure levels.

These findings suggest diet may play a supportive role in managing glaucoma, potentially easing the treatment burden for patients. Still, Edokpa was careful to stress the limits of the research: the results indicate association, not causation.

“Nutrition does not cure glaucoma but it may complement the traditional methods of treatment,” he said.

The study has several limitations. Its cross-sectional design means it cannot establish cause-and-effect relationships, and the relatively small sample size limits how widely the findings can be applied. Dietary intake was also self-reported, making it vulnerable to inaccuracies. To strengthen future research, Edokpa noted that biological samples have already been collected and stored at CAIHR for more objective analysis, pending funding.

Beyond its scientific contribution, the study has practical significance. In a region where glaucoma is both prevalent and devastating, the suggestion that simple dietary changes could reduce disease burden is both accessible and empowering, offering patients a measure of control alongside prescribed treatments.

Edokpa’s work also opens the door for further study, including how combinations of foods might interact and whether dietary effects differ by sex or other demographic factors. As research continues, nutrition could become a more formal part of clinical guidance for glaucoma care.

The takeaway is straightforward. While eye drops and surgery remain essential, diet may also have a role to play.

For patients living with glaucoma, that possibility could prove both hopeful and transformative.