How Everyday Habits May Relate to Glaucoma
Glaucoma can develop quietly, gradually damaging the optic nerve before a person notices changes in their vision. Because early disease often has no obvious warning signs, understanding potential risk factors and attending regular eye examinations are important steps in protecting sight.
Researchers are investigating whether lifestyle habits, including tobacco use and alcohol consumption, may be associated with this condition. A study published in the journal Eye and Vision on October 10, 2026, examined these associations among adults in three sub-Saharan African countries.
The research, titled “Association between alcohol and tobacco use and primary open-angle glaucoma: the Eyes of Africa study,” found higher odds of primary open-angle glaucoma among former and current smokers. Alcohol use was also associated with the disease in several analyses, although those findings were less consistent.
These results offer useful information about possible risk factors, but they do not establish that smoking or drinking directly causes glaucoma.
What Did the Eyes of Africa Study Discover?
The research team analyzed information from 9,418 adults aged 40 and older who participated in the Eyes of Africa: Genetics of Blindness study. The investigation covered Nigeria, Ghana and Malawi between 2017 and 2023.
The study population consisted of 5,189 participants with primary open-angle glaucoma (POAG) and 4,229 control participants. Researchers examined reported tobacco and alcohol use and assessed how these behaviors related to the likelihood of belonging to the glaucoma group.
After adjusting for multiple factors, the researchers reported the following associations between smoking history and POAG:
- Former smokers: 38% higher odds of POAG compared with people who had never smoked.
- Current smokers: 46% higher odds of POAG compared with people who had never smoked.
The association with smoking remained statistically significant in a sensitivity analysis comparing current smokers with people who had never smoked. This additional analysis supported the observed relationship, although it did not prove that tobacco exposure caused the disease.
It is important to interpret these figures correctly. They describe differences in odds, not a 38% or 46% increase in an individual’s absolute probability of developing glaucoma.
What Did Researchers Find About Alcohol Consumption?
The study also identified several associations involving alcohol use. However, the relationship between drinking and glaucoma was less consistent than the relationship observed with smoking.
Compared with participants who had never consumed alcohol, the researchers reported these differences in the odds of POAG:
- Former drinkers: 49% higher odds of POAG.
- Current drinkers: 15% higher odds of POAG.
- Participants whose reported lifetime maximum was more than two drinks in one day: 40% higher odds than participants whose maximum was two drinks or fewer.
- Participants who had consumed alcohol within the previous 30 days: 29% higher odds of POAG.
These comparisons refer to different measures of alcohol exposure. They should not be combined into a single estimate or interpreted as evidence that every drinking pattern carries the same association.
The researchers also found that the relationship involving current alcohol consumption was no longer statistically significant after additional adjustment for body mass index and in further sensitivity analyses. This makes the alcohol findings more difficult to interpret than the smoking findings.
Why Might Smoking Affect the Optic Nerve?
The optic nerve carries visual signals from the retina to the brain. Glaucoma damages the nerve’s retinal ganglion cells and their connections, potentially producing irreversible changes in the visual field.
The study authors discussed several possible biological mechanisms through which smoking might contribute to glaucomatous damage, including reduced blood flow to the eye, oxidative stress and injury to retinal ganglion cells.
Reduced ocular blood flow may be relevant because the optic nerve depends on an adequate supply of oxygen and nutrients. Changes in vascular function could potentially affect the nerve’s ability to withstand other stresses.
Oxidative stress occurs when harmful reactive molecules overwhelm the body’s protective antioxidant systems. This imbalance can damage cells and has been investigated as one possible contributor to several eye diseases, including glaucoma.
However, these proposed mechanisms do not establish exactly how smoking may influence glaucoma development in humans. Additional research is necessary to determine how tobacco exposure, vascular health and other factors interact.
How Could Alcohol Be Connected to Glaucoma?
Alcohol may influence several processes relevant to eye health, including vascular regulation, oxidative stress and intraocular pressure (IOP). IOP is the fluid pressure inside the eye, and elevated pressure is an important risk factor for glaucoma.
Nevertheless, glaucoma can develop even when measured eye pressure falls within the statistically normal range. Likewise, not everyone with elevated IOP develops glaucoma.
The study’s inconsistent findings also mean that alcohol consumption should not be described as a proven direct cause of POAG. Researchers suggested that some participants might have reduced or stopped drinking after receiving a glaucoma diagnosis.
This possibility is known as reverse causality: a health condition or its diagnosis may influence a person’s behavior, rather than the behavior necessarily causing the condition. If participants changed their drinking habits after diagnosis, their reported current alcohol use might not accurately reflect their earlier exposure.
What Are the Limitations of the Research?
The Eyes of Africa study provides information from a substantial sample of adults, but its design has important limitations. Because it was cross-sectional, researchers examined exposure information and disease status without establishing the sequence of events needed to demonstrate causation.
The study also relied on self-reported tobacco and alcohol use. Participants may not always remember past behavior accurately or report it consistently, which can affect the quality of exposure measurements.
Although statistical adjustments can account for measured factors, they cannot eliminate every possible source of bias or confounding. Other characteristics, including age, sex, socioeconomic circumstances and general health, may influence the observed relationships.
The researchers reported that older age, male sex, higher educational attainment and unemployment were also associated with higher odds of POAG. Participants aged 80 and older had 83% higher odds than those aged 40 to 59.
These findings emphasize that glaucoma is influenced by multiple factors. The study does not establish that changing tobacco or alcohol use alone will prevent glaucoma or slow its progression.
Who Should Consider Glaucoma Screening?
People aged 40 and older may benefit from discussing their glaucoma risk with an eye care professional, particularly if they have additional risk factors. A family history of glaucoma, increasing age, elevated IOP and certain optic nerve characteristics can affect an individual’s risk.
Smoking history and alcohol use can also be discussed as part of a broader health assessment. However, lifestyle information should complement rather than replace a comprehensive eye examination.
An ophthalmologist or optometrist may recommend several tests to assess glaucoma risk and identify possible damage:
- Tonometry: Measures intraocular pressure.
- Gonioscopy: Examines the drainage angle to help distinguish different types of glaucoma.
- Dilated optic nerve examination: Allows assessment of the optic nerve for signs of damage.
- Optical coherence tomography (OCT): Provides detailed images of retinal nerve fiber layers and other structures.
- Visual field testing: Checks for areas of reduced peripheral vision associated with glaucoma.
These tests provide complementary information. A normal pressure measurement alone cannot rule out glaucoma, and some people have significant disease before they notice any change in vision.
When Should You Seek Medical Attention?
Arrange a comprehensive eye examination if you have not had your eyes checked, have a family history of glaucoma, or have concerns about your risk. People already diagnosed with glaucoma should continue their recommended monitoring appointments even if their vision feels normal.
Seek urgent medical care if you experience sudden eye pain, a red eye, blurred vision, halos around lights or a severe headache accompanied by nausea or vomiting. These symptoms can indicate an eye emergency, including acute angle-closure glaucoma.
Do not wait for symptoms before seeking routine glaucoma screening. Damage caused by glaucoma may be permanent, making timely assessment particularly important.
Practical Steps for Protecting Your Eye Health
The Eyes of Africa study adds to research examining how smoking, alcohol consumption and other factors may relate to primary open-angle glaucoma. Its findings were strongest and more consistent for smoking, while the alcohol associations require more careful interpretation.
Further prospective studies are needed to determine whether changes in these behaviors can reduce the likelihood of developing glaucoma or slow its progression. Until stronger evidence is available, the study should be understood as identifying associations rather than proving cause and effect.
Reducing tobacco exposure is a sensible step for overall health, and people concerned about alcohol use can discuss appropriate support with a healthcare professional. Neither action replaces glaucoma screening or prescribed treatment.
Your next step: Schedule an eye examination and ask your eye care professional about your personal glaucoma risk. If you smoke, have a history of alcohol use, or have relatives with glaucoma, share that information during your appointment so your clinician can consider it alongside your eye pressure, optic nerve appearance and visual field results.
