Key Takeaways

  • Diabetes’ Systemic Impact: Diabetes affects more than blood sugar, leading to heart disease, nerve damage, kidney disease, hearing loss, oral health issues, and vision problems.
  • Heart Disease Risk: High blood sugar levels can damage heart-related nerves and blood vessels, increasing the risk of heart disease, stroke, and heart attack.
  • Nerve Damage: Prolonged hyperglycemia can lead to nerve damage, causing pain, numbness, and tingling sensations.
  • Kidney Disease: Consistently high blood sugar can harm kidney blood vessels, potentially leading to chronic kidney disease.
  • Hearing Loss: Diabetes-related nerve damage can extend to the ears, potentially causing hearing loss.
  • Oral Health Complications: Elevated blood sugar levels can increase the risk of cavities, tooth decay, gum disease, and tooth loss.
  • Vision Loss Risks: Diabetes can lead to eye damage and vision loss, causing conditions like diabetic retinopathy, glaucoma, diabetic macular edema, and cataracts.
  • Diabetic Retinopathy: This condition damages the retina, potentially leading to vision loss and blindness.
  • Cataracts and Glaucoma: Diabetes can cause cataracts and glaucoma, both of which can impair vision.
  • Regular Eye Exams: Annual eye exams are crucial for early detection and management of diabetes-related eye conditions.

The widespread complications of diabetes

As we know, diabetes affects more than just your blood sugar. Prolonged periods of high blood sugar levels can cause detrimental downstream effects throughout your body, affecting things like your heart, kidneys, nerves, and more. It is important to keep these complications in mind so that you can implement prevention strategies and know what signs and symptoms to look out for. Some health problems that result from diabetes include:

  • Heart disease. When your blood sugar levels are high for extended periods, this can injure the nerves and blood vessels connected to the heart. Likewise, this phenomenon can increase your blood pressure, cholesterol, and triglycerides. When these abnormalities occur, you are at increased risk for heart-related conditions such as coronary artery disease, stroke, and heart attack.
  • Nerve problems. Hyperglycemia (high blood sugar) can also negatively impact your nerves. It damages your nerves, preventing them from sending signals throughout the body. Injury to your nerves manifests as symptoms like pain, numbness, tingling, and more.
  • Chronic kidney disease. Just like the blood vessels to the heart, high blood sugar can damage the blood vessels in your kidneys as well. As a result, the nephrons become dysfunctional, eventually resulting in kidney disease. Advanced kidney disease can only be treated with dialysis or a transplant.
  • Hearing issues. Nerve damage can extend to all parts of your body, including your ears. When this happens in the ears, you may experience hearing loss.
  • Oral problems. When your blood sugar levels are high, your sugar levels are also elevated elsewhere, such as in your mouth. This can lead to bacteria, causing cavities, tooth decay, gum disease, and tooth loss. You may also get infections in your mouth.

Finally, diabetes can also lead to issues with your eyes. Eventually, this can lead to eye damage, vision loss, and blindness if left untreated. Diabetes can cause damage resulting in several diseases, including macular edema, diabetic retinopathy, glaucoma, and cataracts. Each of these conditions can end in vision loss if not managed appropriately. Let’s discuss the mechanisms by which diabetes can impact the eyes and what conditions may occur as a result.

Diabetes and the eye

Like any issue related to diabetes, damage is the result of high blood sugar levels over an extended period of time.

It is unlikely that you will experience something as serious as vision loss when you have high blood sugar levels just for a short period. However, you may experience episodes of blurry vision when switching up your diabetes medication regimen or care. When you experience short-term elevations in blood glucose, this can increase fluid in the eye, causing swelling in your eye tissues. As a result, you may experience blurry vision for a short period of time. Once your blood sugars normalize, your vision should too.

The issue arises when blood sugar levels are increased for prolonged periods. Extended time with hyperglycemia damages the small blood vessels behind your eyes. Injury to these vessels causes them to leak fluid, inducing swelling. New but weaker blood vessels may start to form, which can bleed into other parts of the eye, causing scarring and elevated pressures within the eye. As a result, you may experience one or some of the four eye problems associated with diabetes:

  • Diabetic retinopathy
  • Glaucoma
  • Diabetic macular edema
  • Cataracts

We will continue with discussing each of these conditions, including what they are, their symptoms, and how they are treated.

Types of diabetes-related vision problems

The four main eye diseases associated with diabetes are diabetic retinopathy, diabetic macular edema, glaucoma, and cataracts. These conditions are discussed below.

Diabetic Retinopathy

Diabetic retinopathy relates to the retina, which is the inner lining behind each eye. The purpose of the retina is to detect light and then transform that light into a signal for your brain, allowing you to see. Injured blood vessels can cause them to swell and leak, damaging the retina and leading to diabetic retinopathy.

The beginning stage of this is called non-proliferative diabetic retinopathy, where the blood vessels can bulge, weaken, and leak into the retina. As a result, the macula, a part of the retina, can swell. This is known as macular edema. Consequently, you may experience distorted vision and eventually blindness.

It can then progress into proliferative diabetic retinopathy, in which new blood vessels develop on the retina’s surface. This causes severe vision issues, starting with dark spots in your vision and potentially total blocked vision. Symptoms of proliferative diabetic retinopathy include:

  • Dark sports or shapes in your field of vision
  • Difficulty seeing colors
  • Blurry vision
  • Vision loss
  • Empty or dark areas in your line of sight

Treatment of diabetic retinopathy is aimed at repairing eye injury and trying to prevent blindness. Treatment methods include:

  • Medications like VEGF inhibitors, that can delay or reverse diabetic retinopathy
  • Photocoagulation, a laser therapy that delays new blood vessel growth
  • Vitrectomy, which involves removal of some or all of the vitreous
  • Injectable medications like corticosteroids
  • Retina reattachment

Diabetic Macular Edema

As previously mentioned, diabetic retinopathy can cause diabetic macular edema (DME). This condition occurs when the macular, which is the central portion of the retina, swells. Swelling occurs as the result of high blood sugar levels impacting your eyes’ blood vessels, which leak, build up with fluid, and thicken the retina.

Macular edema is the result of diabetes and can lead to eventual vision loss. Symptoms of it can include blurry vision, dark spots, trouble seeing colors, floaters, seeing straight lines as curved or bent, trouble with sight with bright light, and seeing objects of different sizes with different eyes.

There are several treatments for DME, including:

  • Intravitreal injections, which are injections into your eye’s vitreous humor
  • Photocoagulation, which is laser therapy
  • Vitrectomy


With diabetes, increased blood sugar levels can induce structural changes to your eye lens, which can cause cataracts. Cataracts occur when your eye lens clouds. Though this can happen with age, it can happen earlier if you have diabetes. Symptoms of cataracts include:

  • Blurry or cloudy vision
  • Sensitivity to light
  • Seeing double with a single eye
  • Seeing colors as faded
  • Difficulty seeing at night
  • Seeing halos surrounding light

The impact of cataracts can be mitigated by wearing anti-glare glasses and using bright lighting and magnifying lenses. You can also undergo cataract surgery, which replaces your clouded lens with an artificial lens. It is a short surgery, lasting only about 10 minutes with only about a few hours of recovery.


Glaucoma is yet another eye condition that can be caused by diabetes. It is characterized by pressure buildup within the eye, injuring the eye nerves. With this nerve damage, your eyes cannot signal the images they intake into the brain. There are two main forms of glaucoma:

  • Primary open-angle glaucoma. This glaucoma form occurs most frequently and is painless. Fluid buildup in the eye cannot get released through an eye channel due to blockage, leading to liquid buildup.
  • Angle-closure glaucoma. This glaucoma form occurs when the eye’s iris is too close to the drainage angle. When the drainage angle is blocked, eye pressure increases quickly.

Glaucoma can be asymptomatic but progressive disease causes blurry vision, blind spots, headaches, halos, and sharp pain.

You can treat glaucoma starting with prescription eyedrops, which can decrease fluid production and increase fluid drainage, thus lowering the pressure in the eye. You can also opt for procedures such as laser therapy and surgery.

The importance of regular eye exams

Knowing the risks to your vision when living with diabetes, and having regular eye checkups is essential to preventing and managing vision problems. You should always attend annual eye exams, even if you feel okay and are not experiencing any symptoms. Several of the eye conditions we mentioned above can be present without symptoms, yet early detection is essential to prevent disease progression.

For individuals with type 1 diabetes, you should get an eye exam within five years of getting your diagnosis and yearly thereafter. With type 2 diabetes, you should get an eye exam immediately after your diagnosis. This is because you may have been living with diabetes for years before the actual diagnosis, which could in turn have already damaged your eyes. When you go to your yearly eye exam, you will likely undergo the following if you have diabetes:

  • Retinal imaging
  • Visual acuity testing
  • Dilated eye exam
  • Tonometry

Other management strategies

In addition to attending regular eye checkups, it is important to also ensure you are proactively managing your diabetes and high blood sugar levels. Make sure you are having regular visits with your physician and adhering to your medication and/or insulin regimen as directed. Also implement lifestyle changes that can help manage your blood sugar levels, including eating a nutritious and well-rounded diet, exercising regularly, and maintaining a healthy weight.