Diabetes and eye sight: Ophthalmologist reveals the unseen link between diabetes and fading vision

Behind the routine of glucose checks lies a lesser-known threat — vision loss. Experts warn that diabetes can quietly damage the eye’s blood vessels, triggering early cataract and glaucoma. (Image: Pexels)

Behind the daily routine of glucose checks and diet control, there’s another danger; blindness caused by diabetes. Recent projections published in Frontiers in Endocrinology (2025) reveal that India’s diabetes prevalence could reach nearly 7,000 per 100,000 people. The numbers are concerning, but what’s more worrying is what this means for the eyes.

According to Dr M. B. Dinesh, Consultant Ophthalmologist at Maxivision Super Speciality Eye Hospitals, “High blood sugar quietly alters the eye’s microcirculation. It damages lens proteins, increasing cataract risk, and disrupts fluid drainage, raising eye pressure that triggers glaucoma. The tragedy is that many patients discover it only after substantial vision loss.”

Also Read: Diabetes and blindness: Causes, symptoms and ways to prevent diabetic retinopathy

Diabetes affects the delicate balance of the eye through oxidative stress and damaged blood vessels. Over time, the clear lens of the eye turns opaque, forming a cataract, while increased pressure injures the optic nerve, causing glaucoma. Unlike age-related cases, diabetic cataracts and glaucoma appear earlier and worsen faster.

"Regular eye check-ups and good glycaemic control remain the simplest forms of prevention. Annual dilated eye examinations and stringent blood-sugar management are the cornerstones of saving sight", Dr Dinesh tells Moneycontrol.

Many people dismiss the early warnings until it’s too late. Dr Dinesh shares what to watch out for:

• Frequent changes in your spectacle prescription
• Seeing halos or rings around lights
• Blurred or faded vision
• Mild eye pain or pressure

While cataract surgery can restore clear vision, uncontrolled diabetes raises the risk of inflammation after surgery. Glaucoma, on the other hand, causes permanent damage if ignored.

Also Read: Diabetes: Ophthalmologist explains how simple diet changes can keep your eyesight sharp, eyes healthy

Prevention is better

Experts say most diabetes-related vision loss can be prevented. The American Diabetes Association advises a yearly eye exam with pupil dilation for every diabetic adult. Managing HbA1c below 7%, avoiding smoking, eating a diet rich in leafy greens and omega-3 fats, and regular exercise all help protect the eyes. “Simple lifestyle habits,” notes Dr Dinesh, “can mean the difference between clear vision and irreversible blindness.”

Disclaimer: This article, including health and fitness advice, only provides generic information. Don’t treat it as a substitute for qualified medical opinion. Always consult a specialist for specific health diagnosis.