Type 2 diabetes boosts the risk of infections like cellulitis. This higher risk may be due to several factors, such as the effects of diabetes on the immune system and the skin. Without treatment, cellulitis can cause serious illness.

In type 2 diabetes (T2D), the cells in your body don’t respond well to the hormone insulin. This means that glucose (sugar) cannot effectively enter your cells to be used as energy, leading to increased blood sugar.

Over time, untreated high blood sugar can lead to complications in different organ systems, causing:

  • heart disease
  • kidney damage
  • vision problems

T2D also increases the risk of skin infections like cellulitis. Keep reading to learn about the connection between T2D and cellulitis, serious diabetes symptoms to be aware of, and more.

According to the Centers for Disease Control and Prevention (CDC), 38.4 million people in the United States, or 11.6% of the population, had diabetes in 2021. Of these, the majority have type 2 diabetes (T2D).

People with diabetes have a higher risk of infections in general. This includes infections of the skin, respiratory tract, urinary tract, and other areas of the body.

A 2024 review notes that compared with the larger population, people with diabetes have a 1.5 times higher risk of an infection requiring outpatient care and a two to four times higher risk of infection-related hospitalization.

A 2018 study also found a higher risk of infection in people with diabetes than in the broader population. One of the strongest associations researchers found was between diabetes and the risk of cellulitis.

Cellulitis is a bacterial skin infection. In cellulitis, bacteria enter your body through a break in your skin, such as a cut, ulcer, or burn. From there, the bacteria spread into the deeper layers of your skin and potentially to other tissues.

Initial symptoms commonly include red, dark brown, gray, or purple swollen skin. The skin may feel warm to the touch. Learn more cellulitis symptoms.

Increased blood sugar has been linked to a higher risk of cellulitis. This means that making sure your blood sugar levels are within your target range is important in preventing it.

A 2020 study found that having a hemoglobin A1c (HbA1c) value over 7.5% was associated with a 1.4 times higher risk of cellulitis. The odds of cellulitis increased by 12% for each percent increase in HbA1C value. Other factors linked to a higher risk of cellulitis in the study were:

Why does type 2 diabetes increase the risk of cellulitis?

Researchers have many ideas about how T2D increases infection risk. A big factor is the effect of high blood sugar on the body.

Researchers note that high blood sugar negatively affects several parts of the immune system. When your immune system isn’t working well, it boosts your risk of contracting an infection and also impairs your body’s ability to respond to it.

The skin also plays a big role in protecting the inside of the body from a variety of disease-causing germs. However, high blood sugar can also impair our skin barrier.

A 2022 review reports that the skin barrier is dysfunctional in both animal models of diabetes and in people with T2D. One aspect of this dysfunction is that the skin barrier can become more porous, allowing germs to enter more easily.

Lastly, the bacteria naturally living on our skin, called the skin microbiome, can also raise the risk of cellulitis in people with diabetes.

For example, a 2021 review discusses how several studies note significant differences in the makeup of the skin microbiome in people with and without diabetes. This includes increased levels of Staphylococcus aureus, a potential cause of cellulitis, on the skin of people with diabetes.

While cellulitis doesn’t lead to T2D, a 2024 review reports that some other infections could have an effect on inflammation and insulin resistance that could lead to T2D. Researchers specifically call out the following infections:

There are a variety of serious symptoms of T2D to be aware of. Let’s examine these now.

Serious symptoms related to high blood sugar

While it’s less common in T2D, very high blood sugar levels can lead to a life threatening complication called diabetic ketoacidosis.

Symptoms of diabetic ketoacidosis start slowly and can include extreme thirst and increased urination. If it’s not treated, the following symptoms can come on quickly:

Over time, persistent high blood sugar can lead to several serious health problems in people with T2D. In addition to an increased risk of cellulitis and other infections, these include:

Serious symptoms related to low blood sugar

On the flip side, people with T2D can also have their blood sugar become too low. This could be due to the effects of medication, diet, or physical activity. Some of the symptoms of low blood sugar include:

When blood sugar becomes very low, it can be life threatening, leading to coordination problems, seizures, or loss of consciousness.

Talk with a healthcare professional if you experience cellulitis symptoms such as:

  • an area of skin that’s red, purple, gray, or dark brown and swollen, warm, or painful to the touch
  • fever, with or without chills
  • fatigue

The outlook for people with cellulitis is best when it’s diagnosed and treated early before the infection has a chance to spread further. Due to this, contact a doctor if you notice symptoms of cellulitis.

Additionally, if you frequently have symptoms of high or low blood sugar, make an appointment with your doctor to discuss them.

Medical emergency

Blood sugar that’s become very high (diabetic ketoacidosis) or very low is a medical emergency. Go to the nearest emergency room if you’re having symptoms of severely high or low blood sugar.

Now, let’s answer some additional frequently asked questions about T2D and cellulitis.

When should I be worried about cellulitis?

Seek prompt medical care if you think you have cellulitis. Some common symptoms include a rash and red, purple, or discolored lines branching out from the affected area. The skin may be warm and tender. The infection can spread to other areas of your body, including into the bloodstream, if it remains untreated.

What is the best antibiotic for cellulitis in people with diabetes?

The best antibiotic for cellulitis depends on the type of bacteria causing the infection and the severity of the infection. Doctors may give antibiotics orally or intravenously. Examples of antibiotics used to treat skin infections in diabetes are:

What’s the most common pathogen in diabetic cellulitis?

Common causes of bacterial skin infections in people with diabetes include group A Streptococcus species and Staphylococcus aureus. An increased prevalence of methicillin-resistant Staphylococcusaureus(MRSA) has also been observed in people with diabetes.

Can type 1 diabetes cause cellulitis?

People with type 1 diabetes also have a higher risk of cellulitis. In fact, a 2018 study found that people with type 1 diabetes have a higher risk of serious infections in general.

Having T2D is associated with an increased risk of infections, including the bacterial skin infection cellulitis. This is due to the effects of T2D on factors like the immune system, skin barrier, and microbiome.

Ensuring that your T2D is well managed can reduce your risk of cellulitis. It can also help prevent diabetes complications, including heart disease, kidney damage, and vision issues.

Cellulitis can spread quickly and cause serious illness when not treated, so talk with a doctor promptly if you think you have cellulitis. This is especially true for people with diabetes, who have a higher risk of infection-related hospitalization.