A large Korean health database study found people who swap cigarettes for smokeless nicotine products, like vapes, still face a higher chance of serious eye problems than those who quit nicotine entirely; researchers matched tens of thousands of former smokers and tracked eye disease outcomes over several years to compare risks.
Researchers analyzed national insurance records from South Korea and focused on adults who had smoked traditional cigarettes in the early 2010s and then reported quitting by the end of the decade. From that pool they created a matched cohort with similar ages, genders, health histories, and lifestyles to make a fair comparison between true quitters and those who switched to smokeless nicotine. The final matched sample included more than thirty thousand people and provided a cleaner look at long-term visual health after different quitting choices.
The team watched for a range of eye conditions that matter most to vision: cataracts, glaucoma, age-related macular degeneration, diabetic retinopathy, and disorders that affect focusing. Participants were followed for about 4.6 years on average, giving time for chronic eye problems to emerge and be recorded in the health database. Across the tracking period, the researchers counted over six thousand major eye disease events in the cohort.
When rates were calculated per 1,000 person-years, complete quitters had the lowest rate of eye disease at 41.1 cases, while people who moved to smokeless alternatives had a rate of 44 cases. Statistically, that difference translated into an overall 7% higher risk of major eye disease for those who switched to vaping or other noncombustible nicotine products compared to those who gave up nicotine entirely. That may sound modest, but at the population level it represents a notable shift in risk for conditions that can threaten vision.
The signal was stronger for certain conditions. Those who changed to smokeless nicotine faced a roughly 24% higher likelihood of developing diabetic retinopathy, the disease that harms the tiny blood vessels in the light-sensitive tissue at the back of the eye. They were also about 7% more likely to develop refractive and accommodation disorders, problems that interfere with the eye’s ability to focus clearly. These are not trivial outcomes for people managing diabetes or noticing changes in visual clarity.
“These findings challenge the assumption that substituting noncombustible nicotine or tobacco products for conventional cigarettes is visually harmless,” the researchers noted. The authors were careful to point out limits that matter when interpreting the results: the study used retrospective insurance data and relied on self-reported smoking and vaping behaviors, which can introduce errors or underreporting. That means the work shows association, not definitive cause and effect, but the pattern is consistent enough to raise real concern.
Clinicians and people trying to quit should take the message seriously: replacing combustible smoking with a smokeless product may reduce some harms, but it does not necessarily erase risk across every organ system. Vision appears to be one of the areas where lingering or different risks persist, particularly for people with diabetes or other vascular vulnerabilities. That nuance matters for anyone weighing options like nicotine replacement, vaping, or going cold turkey.
From a public health perspective, the takeaway is straightforward — quitting nicotine altogether remains the safest path for eye health based on this analysis. For smokers considering alternatives, the study suggests careful discussion with healthcare providers, especially for those already at higher risk for diabetic or vascular eye disease. While more research that tracks detailed use patterns and biological measures would help clarify mechanisms, the current evidence nudges toward total cessation as the best choice for preserving vision.
