Poor lifestyle choices can negatively impact glaucoma management. The Glaucoma Research Foundation explains that while a healthy diet can’t prevent or cure glaucoma cure, it can provide evidence-based management benefits.

Foods to Consider When Living with Glaucoma

1.  Fruits and Vegetables

Fruits and vegetables provide abundant amounts of vitamins A and C, as well as the antioxidant carotenoids lutein and zeaxanthin that help protect the optic nerve and other eye tissues from oxidative damage.

A study of 584 women in the American Journal of Ophthalmology found that women who ate at least three daily servings of fruits/fruit juices had a 79% lower risk of developing glaucoma than women who ate less than one serving per day. Specifically, they found a protective effect against glaucoma in women who ate more fresh oranges, fresh peaches, collard greens, kale, carrots, and spinach.

2.  Bananas, Beans, and Avocados

In addition to the fruits and vegetables mentioned above, bananas, beans, and avocados are also viable foods for a glaucoma-friendly diet. They’re high in magnesium, an important mineral for overall health, with a recommended daily intake of 300-400mg. Early research suggests that magnesium may help people with glaucoma by improving blood flow and protecting retinal ganglion cells that process and transmit information to the brain.

3.  Leafy Greens

We know that leafy greens are essential for overall health, often being linked to reduced rates of inflammation, cancer, heart disease, and macular degeneration. But they may also help people with glaucoma. 

Harvard researchers examined dietary data from more than 100,000 people involved in two longitudinal studies, finding that those who ate the leafiest green vegetables, like kale and spinach, had a 20%-30% lower risk of developing primary open-angle glaucoma than those who ate the least leafy greens. While the study only proves an association between leafy greens and reduced glaucoma risk; not a causal link, the association could be due to leafy greens’ high nitrate content. Nitrate converts to nitric oxide in the body, which helps maintain optimal blood flow and, possibly, normal eye pressure. In glaucoma, the optic nerve is damaged from increased eye-fluid pressure or reduced blood flow to the optic nerve.

4.  Nuts and Seeds

Vitamin E protects cells and retinal tissues in the eye from free radical (oxidative) damage, and nuts provide high amounts of vitamin E. Good choices are sunflower seeds (also protective against age-related macular degeneration and cataracts), pumpkin seeds (also high in magnesium and omega-3 fats), almonds, hazelnuts, and pistachios (also high in lutein and zeaxanthin).

5.  Fish

Cold-water fish, such as salmon, sardines, tuna, and halibut, are high in omega-3 fats that have been shown to potentially reduce the risk of eye problems later in life, such as age-related macular degeneration and dry eye disease. Omega-3 fats also lower internal eye pressure related to glaucoma.

6.  Dark Chocolate

Chocolate lovers will be encouraged to hear that a small clinical trial with 30 adults found slightly better vision about two hours after participants ate a bar of dark chocolate. Comparing milk chocolate versus dark chocolate, researchers in JAMA Ophthalmology observed that eating dark chocolate improved the ability to see small and large letters of different contrast, possibly due to improved blood flow from antioxidants called flavonols (a type of polyphenol). 

7.  Tea

Researchers in the British Journal of Ophthalmology observed nearly 1,700 participants from the 2005-2006 Health and Nutrition Examination Survey (NHANES) and found that people who drank at least one cup of hot tea each day had 74% less risk of glaucoma versus those who did not drink hot tea. Further research is needed to understand this association, while no such link was found between iced tea, coffee, decaffeinated tea, or soft drinks and glaucoma risk.

Other Research-Based Dietary Advice

• It is advisable to eat a diet that promotes normal blood pressure and blood sugar, since we know that foods that contribute to obesity, hypertension, diabetes, and other conditions can increase the risk of primary open-angle glaucoma.
• Research shows a possible link between obesity and high intraocular pressure (IOP). While we don’t yet know whether weight loss lowers glaucoma risk, weight loss has shown significant declines in IOP.
• Eating fewer carbohydrates is linked to lower glaucoma risk, whereas eating more carbohydrates is associated with greater glaucoma risk.
• A healthy restriction of calories may stimulate “anti-aging mechanisms” that have a protective effect on the eyes.

“Understanding how diet can impact the risk of glaucoma and following healthy dietary guidelines can play an essential role in the lives of people living with glaucoma,” say researchers from the Glaucoma Research Foundation. 

*Glaucoma Research Foundation. (2021, July 12). Glaucoma + Nutrition: why what you eat matters. Ophthalmology Times. https://www.ophthalmologytimes.com/view/glaucoma-nutrition-why-what-you-eat-matters