In people with diabetes, wounds can take longer to heal. These wounds often appear on the feet and legs. This slow healing can increase the risk of developing infections and other complications.

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A person who manages their diabetes well can improve the rate at which wounds heal and reduce the likelihood of a severe infection.

According to the Centers for Disease Control and Prevention (CDC), about 37.3 million people in the United States have diabetes, which equates to 11.3% of the population.

Many of these people will experience complications as a result of infected wounds.

This article looks at the effects of diabetes on wound healing and considers ways to reduce the risk of complications.

Minor wounds, cuts, and burns are an unfortunate but unavoidable part of life. However, for people with diabetes, these injuries can lead to serious health issues.

Many people with diabetes develop wounds that are slow to heal, do not heal well, or never heal. Sometimes, an infection might develop.

An infection can spread to tissue and bone near the wound or reach more distant areas of the body. In some cases, if a person does not receive emergency care, an infection can be life threatening or even fatal.

Even when an infection does not develop in a wound, slow healing can adversely affect a person’s overall health and quality of life. Cuts or injuries on the feet or legs can make walking difficult and lead to pain when exercising.

It is essential that people who have diabetes keep their blood sugar levels under control to reduce the risk of slow-healing wounds and complications, including foot ulcers.

According to some reports, foot ulcers will develop in about 1 in 4 people with diabetes. Foot ulcers are painful sores that can ultimately lead to foot amputation. If a person with a foot ulcer has peripheral neuropathy, a form of nerve damage that can be associated with diabetes, they may not feel any pain.

According to a 2020 article, diabetes contributes to 25–90% of all amputations within studied populations. Other research has shown that the risk of diabetes-related amputation is more than three times higher among Black Americans than among people belonging to other racial and ethnic groups.

Research shows a clear correlation between blood glucose and wound healing. Diabetes impairs how the body produces or responds to insulin, a hormone that allows the cells to take and use glucose from the bloodstream for energy. This disruption to insulin makes it more difficult for the body to manage blood glucose levels.

When blood glucose remains permanently high, it impairs the function of white blood cells. White blood cells are central to the role of the immune system. When white blood cells are unable to function correctly, the body is less able to fight bacteria and close wounds.

Uncontrolled diabetes may also affect circulation, causing blood to move more slowly, which makes it more difficult for the body to deliver nutrients to wounds. As a result, the injuries heal slowly or may not heal at all.

Diabetes can also cause diabetic neuropathy, which can affect wound healing. Uncontrolled blood glucose can damage the nerves, numbing sensations in the area. This may mean that people with diabetes who sustain trauma to their feet might not be aware of the injury.

If a person is not aware of an injury, they may not receive treatment, which might allow the wound to worsen. A combination of slow healing and reduced sensation in the area significantly increases the risk of infection.

People with either type 1 or type 2 diabetes have an increased risk of developing a bacterial infection in the wound.

Factors that may increase this risk include:

  • impaired sweating
  • dry and cracked skin
  • toenail infections
  • foot abnormalities, such as Charcot’s foot

Diabetes might also affect wound healing in other ways, such as:

  • reducing the production of growth and healing hormones
  • decreasing the production and repair of new blood vessels
  • weakening the skin barrier
  • reducing collagen production

People who experience poor wound healing due to the effects of diabetes on the nerves and blood vessels might also experience other complications. These include heart disease, kidney disease, and eye problems.

If an untreated wound becomes infected, the infection may spread locally to muscle and bone. Doctors call this osteomyelitis.

If an infection develops in the wound and goes untreated, it can progress to the stage of gangrene. Gangrene is a common cause of amputations in people who lose limbs as a result of diabetes.

Sometimes, people with uncontrolled infections develop sepsis, which occurs when an infection spreads into the bloodstream. Sepsis can be life threatening.

People with diabetes can use specific strategies to minimize the time it takes for a wound to heal. These include managing blood glucose, practicing thorough foot care, and treating wounds as they occur.

Foot care for diabetes

Appropriate foot care includes:

  • washing the feet daily
  • patting the skin dry before applying moisturizer
  • avoiding walking barefoot
  • trimming the toenails carefully
  • wearing comfortable shoes
  • inspecting the feet and looking inside the shoes daily
  • having a doctor check the feet at each visit

Wound treatment

It is essential that people with diabetes carefully monitor their wounds. Although wounds might heal slowly, it is not normal for them to remain open for several weeks. Equally, they should not spread, ooze, or become extremely painful.

An infection might not develop in every ulcer or wound, but people should still take steps to prevent infection. The first step is to clean the wound and cover it with a clean bandage, repeating this daily.

It might be a good idea for people with diabetes to wear shoes and socks when walking around, especially if a wound has developed. Being barefoot increases the risk of infection.

People with diabetes should seek treatment if a wound develops on their foot and does not heal. A person will often need to take antibiotics to combat any infections, and they might require hospitalization if the wound is severe.

Glucose control

People who manage their blood glucose levels are less likely to experience severe wounds that do not heal.

Although people with type 1 diabetes will need to take insulin throughout their life to control their blood sugar, people with type 2 diabetes have more options. As well as taking insulin and other medications, making certain lifestyle adjustments, such as eating a nutritious diet, exercising regularly, and reaching or maintaining a moderate weight, may substantially improve a person’s blood sugar levels.

These lifestyle changes may even allow a person to manage diabetes without medication.

People with type 1 or type 2 diabetes can benefit from a carbohydrate-controlled diet. It may be helpful to talk with a doctor, who can suggest a meal plan that includes the specific number of carbs that a person should eat each day.

When a person has diabetes, a wound that does not heal can quickly become life threatening. Prompt treatment and effective glucose management are essential for people with slow-healing wounds to have a positive outlook.

People with diabetes should contact a doctor immediately if they develop serious or painful wounds that do not heal after several days, or if an infection seems to have developed.

A combination of aggressive antibiotic treatment, wound cleaning, surgical removal of dead tissue, and more effective glucose control may help. If the wound does not respond to treatment, amputation may be necessary.

People should take preventive steps before wounds develop to reduce the risk of wound healing complications.

Below, we answer some commonly asked questions about the effects of diabetes on wound healing.

What does a diabetic ulcer look like?

A diabetic foot ulcer looks like an open wound with no skin covering, and it is usually circular. If gangrene develops, the tissue may look black. A person will typically not experience pain, which often leads to a delay in diagnosis.

How long does a diabetic wound take to heal?

Diabetic wounds can take a while to heal. A 2017 study involving 105 people with diabetic foot ulcers reported that the median time from starting medical care to healing was 75.5 days, excluding the wounds that did not heal. However, research also shows that some medications may be able to reduce this time significantly.

Is there a way to save a limb if gangrene develops?

Gangrene typically refers to a critical loss of blood supply with tissue destruction and, possibly, infection. Gangrenous tissue requires surgical removal. However, if a doctor diagnoses the condition early, and there is limited risk to the tissue, a full amputation might not be necessary. Early intervention and detection are crucial.