Woman getting an eye exam from a doctor


FAQ: "How will diabetes affect my eyes?" Here are the answers. 


High blood glucose levels have a negative impact on almost every organ in the body, and that includes the eye. High glucose causes the lens to swell. This is generally temporary. But, the effects of high blood sugar over time can lead to one or more of the following common eye diseases for people with diabetes.

Retinopathy occurs in approximately 30% of all people with diabetes over the age of 40. If your blood glucose remains high over time, it can impact the vessels in the back of your eye which can leak and swell. New blood vessels can grow and these vessels are generally weak and can leak into the middle part of the eye, leading to scarring or high pressure within the eye. Retinopathy is the most common cause of vision loss in people with diabetes. In most people with type 1 diabetes and around 60% of people with type 2 diabetes eventually develop some level of retinopathy. 

Cataracts are a clouding of the lens of the eye. Most people will develop cataracts as they age, but it is 2-5 times more likely in people with diabetes and generally occurs at an earlier age. 

Glaucoma is also more common in people with diabetes. Glaucoma is a rise in the pressure in the eye and can impact the optic nerve – the part of the eye that connects the eye to the brain.

What are the signs and symptoms of eye disease?

Changes in the eye often occur without any signs or symptoms. That is why a yearly dilated eye examination by an optometrist or ophthalmologist is so important. They can see into the back of your eye and determine if any changes are occurring.

As eye disease progresses you can have some of the following signs and symptoms:

  • Blurry vision
  • Wavy vision
  • Dark areas in the central part of vision
  • Floaters (spots of dark strings in the line of vision)
  • Flashes of light

What can I do to avoid eye disease?

  • Have an annual dilated eye exam. Many of the eye diseases occur without any signs or symptoms initially. A dilated eye exam can reveal any changes in your eyes and therapy can be started early and prevent vision loss!
  • Manage glucose levels with a target of less than 130 mg/dl before eating and less than 180 mg/dl 2 hours after eating. Another way to look at targets is if you wear a continuous glucose monitor you should strive to be in target range (70-180 mg/dl) 70% of the time.
  • Maintain a blood pressure within target range of less than 130/80 mmHg. This target may differ slightly, so talk with your health care provider about your blood pressure target.
  • Your blood cholesterol and triglyceride levels should also be in target range. Talk with your health care professional about where those numbers should be for you!
  • Eat a healthy diet. Lots of fresh vegetables, fresh fruit, lean meats, low fat dairy and whole grains. Avoid eating a high amount of processed foods like chips, white flour products and boxed dinners.
  • Have a daily activity plan. Enjoy a walk with the dog, a swim in the local pool, a bike ride, gardening, aerobics or any type of movement you enjoy.
  • If you have questions or concerns or need help figuring out how to do all this – talk with your diabetes care team. A diabetes educator can help you put all the pieces together!

How is eye disease treated?

The treatment for eye disease varies depending on the disease itself and the extent of the disease. For example, glaucoma may require drops in the eye, retinopathy may require laser surgery or there may be a need to take injections in the eye.

Take home message

Taking care of your health and following up with an annual dilated eye examination can help halt the progression and reduce the chance of vision loss. Keep on top of it and make sure to see your eye care provider for a dilated eye examination at least once yearly. If you do have vision loss, seek the help of a low vision specialist to help you find tools to enhance your vision.