Causes and Risk Factors of Diabetic Neuropathy

It can affect different types of nerves

Diabetic neuropathy is a complication of long-term diabetes mellitus, especially when blood sugar is not well controlled. It is caused by nerve damage that can occur with type 1 diabetes or type 2 diabetes

This article describes the risk factors, types, and causes of diabetic neuropathy. 

Person with diabetes checking their blood sugar at home

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Common Types and Causes 

Diabetic neuropathy affects the peripheral nervous system and includes four types of nerve damage. They can begin at different times—and some people with diabetes might experience a few effects of diabetic neuropathy rather than all of them.  

These include: 

  • Peripheral neuropathy, which involves the small nerves in the hands and feet, is usually approximately equal on both sides of the body
  • Proximal neuropathy, which affects nerves that control large muscles in the body, such as in the thighs and shoulders, is not usually symmetrical
  • Autonomic neuropathy, which causes symptoms that interfere with digestion, urination, blood pressure, and heart function
  • Focal neuropathy, which affects the control of one area of the body, like the arm, and not necessarily both sides of the body 

Diabetic neuropathy affects sensory nerves and motor nerves, causing pain, loss of sensation, and muscle weakness.

How Nerve Damage Happens 

Neuropathy in diabetes occurs due to both demyelination and axonal injury. Demyelination is damage to the protective fat layer (myelin) surrounding the nerves. Axonal injury is the destruction of the nerve itself.

Several factors are associated with diabetic neuropathy:

  • Microvascular compromise: The small blood vessels that supply oxygen-rich blood to the nerves can become narrow or completely blocked due to vascular damage from diabetes.
  • Inflammation: Areas of nerve damage in diabetic neuropathy often have inflammatory cells.
  • Metabolic abnormalities: Chemical alterations lead to the production of sugars and proteins that have been found to injure nerves in diabetic neuropathy.

All these factors prevent the nerves from getting the nutrients they need to function properly and survive. Over time, the nerves degenerate. Eventually, the muscles supplied by these nerves can atrophy (wither away).


Research shows that long-term metabolic changes of diabetes can affect how certain genes are expressed. With these changes, some proteins needed to maintain healthy nerves are no longer produced. This change in gene expression has been associated with diabetic neuropathy.

Researchers are looking at potential ways to use this information to develop treatments that could slow down the progression of diabetic neuropathy. 


Diabetes causes vascular changes in small blood vessels throughout the body. This causes a decrease in blood supply to structures like the nerves, eyes, and kidneys.

Low blood supply means that these tissues don’t get the oxygen and nutrients that they need. This eventually leads to cell and tissue degeneration, including the type of nerve degeneration that contributes to diabetic neuropathy. 

Additionally, the cardiovascular system is affected by autonomic diabetic neuropathy. This can lead to irregularities in blood pressure regulation and heart rate, which raise your risk of serious complications, such as heart disease and stroke.


Cardiovascular complications of diabetes include heart disease, high blood pressure, peripheral vascular disease, and autonomic changes.

Lifestyle and Risk Factors

Many lifestyle factors can increase the risk of diabetic neuropathy. Uncontrolled diabetes can accelerate the development of diabetic neuropathy.

Lifestyle factors that may cause nerve damage, inflammation, or vascular problems can compound the risk of developing neuropathy and experiencing serious nerve damage that adds to the damage of diabetic neuropathy. 

Factors that can increase the risk of neuropathy are:

  • Irregular blood sugar or high blood sugar 
  • Excess alcohol consumption
  • Smoking
  • Malnutrition (not getting enough calories, vitamins, minerals, protein, fat, and carbohydrates in the diet)
  • Taking medication that can cause neuropathy, such as chemotherapy 
  • Untreated health issues, like lung disease 
  • Environmental toxin exposure

If you have diabetes, you might develop diabetic neuropathy even if you control your blood sugar levels. But you can lower the risk by adopting some consistent lifestyle strategies. 

Ways to reduce the risk and severity of diabetic neuropathy include:

  • Check your blood sugar on a schedule determined by your healthcare provider.
  • Follow a diet and medication plan to keep your blood sugar at healthy and stable levels.
  • Maintain a diet with adequate nutrients, such as carbohydrates, protein, fat, vitamins, and minerals.
  • Keep up with your visits to your healthcare provider and get medical problems checked out and treated.
  • Do not smoke or drink alcohol.


Diabetic neuropathy can be a complication of uncontrolled type 1 or type 2 diabetes. The nerve damage can affect peripheral nerves, proximal nerves, and autonomic nerves, and it can cause focal areas of nerve damage as well. Sensory and motor nerves are impacted by diabetic neuropathy.

Over time, this condition develops due to diabetes-induced vascular disease, inflammation, and metabolic changes. Some risk factors, including poorly controlled blood sugars, smoking, alcohol, and neurotoxic medication exposure, can compound the risk of developing diabetic neuropathy.

A Word From Verywell 

If you have been diagnosed with diabetes, it’s important for you to be familiar with the potential complications.

Anyone who has diabetes can develop diabetic neuropathy, but poorly controlled blood sugars, as well as other factors that can contribute to any type of neuropathy (like alcoholic neuropathy), can increase the likelihood of developing severe effects of diabetic neuropathy.

Talk to your healthcare provider about what you can do to reduce your risk of diabetic neuropathy.

Frequently Asked Questions

  • Why does diabetes cause neuropathy?

    Diabetes leads to metabolic changes, vascular compromise, inflammation, and genetic alterations that all contribute to many complications, including nerve damage. 

  • What else causes neuropathy other than diabetes?

    Besides diabetes, other common causes of neuropathy include chronic alcohol use, nutritional deficiency, medication side effects, organ failure, and nerve damage from industrial chemical exposure. 

  • What causes diabetic neuropathy to flare up?

    Diabetic neuropathy is not a condition that has flare-ups, but the painful symptoms can be more severe when you are dehydrated or while you have another illness, such as an infection. 

  • Can diabetic neuropathy cause swelling?

    In general, diabetic neuropathy does not cause swelling. Diabetes makes you susceptible to infections, and loss of sensation due to diabetic neuropathy can make you unaware of an infection.

    Infections may cause swelling of the affected area—this can be a sign that an infection is progressing to a dangerous degree. 

4 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. Pathak R, Sachan N, Chandra P. Mechanistic approach towards diabetic neuropathy screening techniques and future challenges: A review. Biomed Pharmacother. 2022;150:113025. doi:10.1016/j.biopha.2022.113025

  2. Hall BE, Macdonald E, Cassidy M, et al. Transcriptomic analysis of human sensory neurons in painful diabetic neuropathy reveals inflammation and neuronal loss. Sci Rep. 2022;12(1):4729. doi:10.1038/s41598-022-08100-8

  3. Wang X, Luo L, Xing J, et al. Assessment of peripheral neuropathy in type 2 diabetes by diffusion tensor imaging. Quant Imaging Med Surg. 2022;12(1):395-405. doi:10.21037/qims-21-126

  4. Hansen CS, Suvitaival T, Theilade S, et al. Cardiovascular autonomic neuropathy in type 1 diabetes Is associated with disturbances in TCA, lipid, and glucose metabolism. Front Endocrinol (Lausanne). 2022;13:831793. doi:10.3389/fendo.2022.831793

By Heidi Moawad, MD
Heidi Moawad is a neurologist and expert in the field of brain health and neurological disorders. Dr. Moawad regularly writes and edits health and career content for medical books and publications.