Diabetes and Cataracts: What Is the Relationship

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If you have diabetes, you may also find yourself contending with cataracts (a clouding of the lens of the eye). While anyone can develop cataracts, particularly as they age, high blood sugar from diabetes can damage the lens and cause cataracts to occur sooner.

What's more, if you have diabetes, you may also be prone to more complications if you undergo cataract removal.

This article will discuss the relationship between diabetes and cataracts, including what to know about managing these two conditions together.

A person having an eye examination with an eye doctor

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Connection Between Diabetes and Cataracts

Those with diabetes are more apt to develop cataracts. For those under age 65 with diabetes, cataracts occur3 to 4 times more frequently. Likewise, for those over age 65, cataracts are twice as prevalent for those who have diabetes.


People with diabetes are prone to cataracts because high blood sugar (glucose) levels can damage the lens. This can cause structural changes that can speed the development of cataracts that otherwise would not be a problem until later in life.

Here's how it works. High blood sugar levels can cause the lens to swell and blur vision. Also, an enzyme in the lens converts sugar into a sugar alcohol known as sorbitol. As the sorbitol collects, it causes the lens to become cloudier and objects to appear blurry as a result.

During cataract removal surgery, people with diabetes may also be at increased risk for certain problems. One such problem is a heightened risk of developing diabetic retinopathy. With this, blood vessels in the light-sensitive retina are damaged by high blood sugar, and abnormal, new blood vessels develop. These new blood vessels can then leak blood onto the retina and damage it.

Diabetic retinopathy can cause vision loss for some. In a study, however, this mostly resulted in mild to moderate diabetic retinopathy cases.

Those with diabetes are also at higher risk of developing certain complications associated with cataract removal. Namely, you may be more likely to develop what's known as diabetic macular edema, where the center portion of the retina (the macula) swells. Symptoms of this may include:

  • Straight lines appearing wavy
  • Colors appearing muted
  • Objects appear to be different sizes depending on which eye is used for viewing

Treatment and Management of Cataracts with Diabetes

If you have diabetes and have developed a cataract, you will likely need surgery to remove them. Modern cataract surgery is usually done with a process known as phacoemulsification. In this, the cataract is broken apart with the aid of ultrasound energy and removed through a tiny incision. The natural lens is then replaced with a clear artificial one.

Unfortunately, people with diabetes tend to have more complications from such cataract surgery. Those who fare the worst are people who undergo cataract removal with preexisting macular edema or who have active proliferative diabetic retinopathy, in which abnormal new blood vessels are forming on the retina.  

After the surgery, the ophthalmologist (eye doctor) will likely prescribe medication to control inflammation, such as topical steroids or nonsteroidal anti-inflammatory drugs (NSAIDS). These can help to prevent or treat macular swelling.

The ophthalmologist will also monitor you closely as you're recovering to help ensure that you're not developing diabetic retinopathy. If they do see signs, the ophthalmologist will promptly refer you to a retinal specialist for follow-up.


Ideally, keeping cataracts from forming in the first place is preferable to treating them. Prevention can include:

  • Keep your blood sugar levels in the target range, which is usually between 80 and 180 milligrams per deciliter (mg/dL).
  • Avoid or quit smoking.
  • Protect your eyes from ultraviolet rays with sunglasses.
  • Consume lots of fruits and vegetables rich in valuable nutrients.
  • Increase your activity level, which can both lower blood sugar and protect your vision.


If you have diabetes, you will develop cataracts earlier in life than most people without the condition. Those under age 65 with diabetes are 3 to 4 times more likely to develop cataracts early on. That's because high sugar levels cause the lens to swell and a substance known as sorbitol to collect there. The result is that the lens becomes cloudy and your vision blurry.

If you have the cataract removed, you are also at increased risk for complications such as the development of macular edema or diabetic retinopathy.

If you undergo lens removal and replacement, the ophthalmologist and anesthesiologist provider will take the management of your blood sugar levels into account in order to perform the procedure safely. Afterward, you will be carefully monitored and given medication to help reduce the risk that you don't develop macular edema or diabetic retinopathy.

A Word From Verywell

Developing a cataract when you already have diabetes may seem daunting. The good news is that cataract surgery is a very safe procedure, and special precautions can be taken to help ensure that your diabetes is controlled and your vision is ultimately preserved.

6 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Kiziltoprak H, Tekin K, Inanc M, Goker YS. Cataract in diabetes mellitus. World J Diabetes. 2019;10(3):140-153. doi:10.4239/wjd.v10.i3.140

  2. American Diabetes Association. Curious about cataracts?

  3. American Academy of Ophthalmology. Diabetes and cataracts.

  4. Tham YC, Liu L, Rim TH, et al. Association of cataract surgery with risk of diabetic retinopathy among asian participants in the singapore epidemiology of eye diseases study. JAMA Netw Open. 2020;3(6):e208035. doi:10.1001/jamanetworkopen.2020.803

  5. National Eye Institute. Macular edema.

  6. Centers for Disease Control and Prevention. Diabetes and vision loss.

By Maxine Lipner
Maxine Lipner is a long-time health and medical writer with over 30 years of experience covering ophthalmology, oncology, and general health and wellness.