Diet Soda and Diabetic Eye Disease: What Patients Should Know
Drinking diet soda may be associated with a higher risk of proliferative diabetic retinopathy (PDR)—an advanced form of diabetic eye disease that can lead to severe vision loss—according to research published in Clinical and Experimental Ophthalmology.
In this study of adults with diabetes, individuals who consumed more than four cans (about 1.5 liters) of diet soft drinks per week were found to have approximately double the risk of developing proliferative diabetic retinopathy compared with those who did not consume diet soda. Notably, the study did not find a similar association between regular, sugar-sweetened soft drinks and diabetic retinopathy.
This was the first study to specifically evaluate the relationship between soft drink consumption and microvascular complications of diabetes, including diabetic retinopathy and diabetic macular edema.
Key Study Details
Participants: 609 adults with diabetes (primarily type 2) treated at a tertiary eye hospital
Average age: 64.6 years
Findings:
24% had proliferative diabetic retinopathy
High diet soda consumption was linked to a 2.5-fold increase in the odds of having PDR, even after adjusting for traditional risk factors such as diabetes duration, smoking, and body mass index
Regular soft drink consumption was not associated with the presence or severity of diabetic retinopathy
Why Might Diet Soda Be a Concern?
Although the exact biological mechanism is not yet understood, some researchers believe artificial sweeteners may disrupt normal metabolic signaling—potentially increasing hunger, calorie intake, and cardiometabolic risk over time. Previous research has linked diet soda consumption to type 2 diabetes, cardiovascular disease, and metabolic syndrome.
Important Limitations
This was a cross-sectional study, meaning it captures a single point in time. As a result, it cannot prove that diet soda directly causes diabetic retinopathy. Long-term studies are needed to better understand whether diet soft drinks contribute to disease progression or whether consumption patterns change after diagnosis.
Takeaway for Patients
Diet soft drinks are often marketed as a healthier alternative to sugary beverages, but growing evidence suggests they may not be risk-free—particularly for individuals with diabetes.
At Wagner Kapoor Institute, we encourage patients with diabetes to:
Maintain regular dilated eye exams
Focus on overall blood sugar control
Discuss dietary habits, including beverage choices, with their healthcare team
Protecting your vision starts with informed choices and proactive eye care.
Clin Exp Ophthalmol. 2018;46:767-776. Full text
