How Diabetes Affect Your Eyes and Eye Care Tips

Medically Reviewed by Michael Dansinger, MD on May 21, 2023
5 min read

When you have type 1 or type 2 diabetes, you're more likely to have eye problems than someone without it. High blood sugar can damage the tiny blood vessels in your eyes over time. That can lead to an eye disease called diabetic retinopathy. High blood sugar can also lead to cataracts and glaucoma. So take care of your diabetes -- and keep up with annual eye exams -- to take care of your eyes.

Diabetic retinopathy: At some point, nearly 1 out of 3 people with diabetes has retinopathy -- damage to the blood vessels in the retina. That’s the lining at the back of your eye. Non-proliferative retinopathy, which doesn't usually threaten your eyesight, is most common.

If you continue to have high blood sugar over several years, though, you could go on to have a more severe disease known as proliferative diabetic retinopathy. It's called "proliferative" because new blood vessels start to grow on the surface of the retina. These blood vessels are fragile and can leak blood or fluid. This causes scarring of the retina and long-term vision loss.

Diabetic retinopathy may also cause macular edema. This happens when fluid leaks into the part of the retina that helps give you sharp, central vision. You need that for reading, driving, and seeing fine details. Instead, things look blurry.

Many studies have shown that you can cut your odds of losing your vision from retinopathy and macular edema with strict control of your blood sugars, blood pressure, and cholesterol.

If you find and treat diabetic retinopathy early, you can slow or even reverse some forms of vision loss. If you have diabetes, you should see an eye doctor at least once a year. If your annual exams are normal, you may be able to have follow-up exams every 2-3 years.

There are many ways to treat proliferative diabetic retinopathy. Your doctor may target the retina with a special laser to shrink the new blood vessels. These fragile blood vessels could tear, causing bleeding in your eye. This laser procedure may keep your vision better for longer. It works best if used before the fragile new vessels have started to bleed.

A procedure called a vitrectomy may be used to remove the clear gel of the eye, called the vitreous if it becomes clouded by blood.

You may also need treatment to repair a detached retina or damaged macula caused by this new blood vessel growth.

If you have macular edema, laser surgery or drugs placed inside your eye can slow leaking around the macula.

Diabetes and cataracts: You're more likely to have cataracts -- and at a younger age -- if you have diabetes. Cataracts cloud your eye's lens and cause blurred vision. If you have mild cataracts, sunglasses and glare-control glasses can help. If it's severe, cataract surgery replaces the cloudy lens with a human-made lens to improve your vision.

Diabetes and glaucoma: Having diabetes doubles your odds of glaucoma, a condition that puts added pressure in your eye. This extra pressure can damage the retina and the optic nerve, the main eye nerve for sight. You likely won't have symptoms early on. Some people slowly lose vision or see bright halos or colored rings around lights. Glaucoma is treated with prescription eyedrops to lower eye pressure. In some cases, you may need laser treatment or surgery.

Protect your eyesight with these eye care tips:

1. Manage your blood sugar.

One of the best things you can do for your eyes is to keep your blood sugar at near-normal levels. Steady blood sugar control can slow the damage to the tiny blood vessels in your eyes. This helps prevent or delay the start of eye problems linked to diabetes. Two to four times a year, have an A1c blood test, which measures your glucose levels for the past 2 to 3 months. This helps your doctor to better plan your treatment. Aim for a test result of around 7% or less.

2. Manage your blood pressure.

Control your blood pressure to help slow or prevent eye disease caused by diabetes. Have your blood pressure checked by your doctor at every visit. If a low-salt diet, staying at a healthy weight, and exercise aren't enough to keep it under control, you may need drugs to bring it down to a healthier level. The goal for most people with diabetes is blood pressure of less than 130/80.

3. Have yearly "dilated" eye exams.

An eye doctor needs to widen your pupils with special eyedrops to look for early signs of damage to tiny eye blood vessels. Get a full eye exam every year, so your eye doctor can find and treat problems early.

If you are pregnant or planning to get pregnant, get an eye exam early in your pregnancy and stay in touch with your eye doctor throughout your pregnancy.

4. Watch for warning signs.

The sooner you notice an eye problem, the more likely treatment will help. Call your doctor if you have any of these symptoms:

  • Blurry, cloudy, or double vision
  • Flashing lights or rings around lights
  • Blank, dark, or floating spots in your vision
  • Pain, pressure, or constant redness in your eyes
  • Trouble seeing signs or straight lines
  • Trouble seeing out of the corner of your eye
  • Any sudden change in your vision

5. Quit smoking.

Smoking damages your blood vessels and raises your odds of eye problems, which are already higher because you have diabetes. If you smoke, get help from your doctor, a support group, or a smoking cessation program so you have strength to quit -- and stay smoke-free. The American Cancer Society and other groups sponsor 800-QUIT-NOW, a website and phone service that gives free advice and support for quitting.

6. Take heart: Diabetes care and eye care work together.

It doesn't take a lot of extra work to take care of your eyes with diabetes. The steps you take to manage diabetes also help keep your eyes healthy. Follow your diabetes meal plan, get enough exercise, and take any diabetes drugs as prescribed. This helps keep your blood sugar levels healthy -- and gives you the best possible chance of keeping your eyesight strong.