Glaucoma: Catching the Silent Thief

Proactive Steps to Protect Your Vision

Left: Normal vision; Right: Simulated tunnel vision due to advanced stage glaucoma.

Glaucoma is often described as the “silent thief of sight” because the symptoms of vision loss start off as barely noticeable changes in contrast, often in only one eye first, and thus the fellow eye fills in what’s missing. By the time central vision decline is noticed, it’s far too late and vision that is lost from glaucoma currently cannot be recovered.

So how do you catch a thief?

An eye exam to detect the disease before it is symptomatic is important.  Both glaucoma suspects and definite glaucoma patients need to be monitored. During these visits, the eye care specialist will measure the intraocular pressure (IOP), assess the optic nerve, and perform visual field testing. A combination of test results often with small change over time is needed to confirm the diagnosis.

While glaucoma treatment may involve medications, laser, or surgery, lifestyle choices also play a significant role to maintain IOP control. A well-balanced diet rich in antioxidants, such as green leafy vegetables and colorful fruits, can support overall eye health. According to one large population health study, leafy greens provide dietary nitrate, which has been associated with lowering risk of glaucoma progression by 20-30%. Additionally, supplementation with omega-3, a fatty acid commonly found in fish, nuts, and certain plant oils, has been shown to lower IOP by a small amount of about 1 mmHg. Finally, in one population health study, those who drank a daily hot cup of tea were less likely to have glaucoma vs. those that did not.

Lifestyle recommendation

Strength of Evidence


Fresh fruits (Vit A, Vit C)

Low - survey data

Giaconi et al, Am J Ophthalmol, 2014

Leafy green vegetables

Moderate - prospective cohort

Kang et al, JAMA Ophthalmol, 2017

Hot tea (caffeinated)

Low - survey data

Wu et al, Br J Ophthalmol, 2018

Omega-3 supplements

High - randomized controlled trial

Downie et al, Transl Vis Sci Technol, 2018

Smoking cessation

Moderate - prospective cohort - though data is strongest in those who never smoked

Pérez-de-Arcelus et al, Medicine (Baltimore), 2017

Aerobic exercise

Moderate - prospective cohort - approximately 2-3 mmHg lower immediately after joggin

Natsis et al, BMC Ophthalmol, 2009


Regular physical activity helps maintain healthy blood flow to the optic nerve, reducing the risk of progression. However, one should avoid lifting heavy weights without breathing (valsalva), or keeping the eyes below the heart level for long periods. Both situations are associated with higher pressures in the eye, which may exacerbate glaucoma. Additionally, managing stress through relaxation techniques can contribute to better eye health, as high stress levels can impact IOP.

And if you haven’t already quit smoking - here’s one more reason - smoking has been significantly associated with increased risk of glaucoma. On the other hand, marijuana use has been touted in the popular media as a treatment for glaucoma. One study showed marijuana can reduce IOP, however only for a short time from the THC and only in 60-65% of patients; thus it is not recommended and has more side effects than benefits for glaucoma.

Ultimately, whether or not certain lifestyle activities can affect IOP and therefore glaucoma progression can vary from person to person. One way to determine how different lifestyle choices can impact IOP is to try home IOP monitoring with Xala Health. Please consult your ophthalmologist if home IOP monitoring is right for you.

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