Diabetes and Infections

If you have diabetes, your body is more likely to develop an infection, and those infections are also more prone to spread quickly, get worse, or require medical care. Elevated blood sugar levels can weaken the body’s immune system, leaving it more susceptible to attacks by germs and other pathogens. The resulting infections, which can happen most anywhere in the body, can range from annoying to life-threatening, but if an open sore or wound is affected, seek medical help immediately.
Why Diabetes Increases Infection Risk
High blood sugar, also known as hyperglycemia, is the hallmark symptom of diabetes, and it puts extra stress on your body. That can impair the body’s immune system and allow bacteria and fungi to thrive from your mouth down to your feet.
“When the body is under high levels of stress, the immune system can be affected, resulting in a weaker and less robust response to infection,” says Lisal Folsom, MD, the medical director of the adult endocrinology division at the Wendy Novak Diabetes Institute at Norton Healthcare in Louisville, Kentucky.
- Higher levels of inflammation, which damage the body’s organs over time
- Blood vessel damage, which reduces healthy blood flow
- Neuropathy or nerve damage, which makes you more likely to tear your skin
The first line of defense against infections is keeping your blood sugar levels as close to your target range as possible. Healthy glucose levels are the best way to make sure that your body can give 100 percent when fighting harmful germs, making it easier to recuperate.

Foot Infections
Reduced sensation stems from issues like peripheral neuropathy, or damage to the nerves in your extremities.
The right treatment will depend on the type of infection a person has and how severe it is. Your provider may need to drain the wound, cut away infected tissue, or prescribe antibiotics.
How to Prevent Foot Infections
- Wash, dry, and examine your feet thoroughly every day. Check your feet for any signs of injury, even small ones like redness, blisters, and cuts.
- Wear comfortable shoes and socks and don’t go barefoot. You’ll reduce your chance for blisters or other injuries.
- Trim your toenails straight across. Well-trimmed nails can prevent cuts. Use a nail file to smooth out sharp edges, too.
- Never remove corns or calluses at home. See your doctor or a podiatrist for help to reduce the risk for injury.
- See your doctor regularly. Reach out at the first sign of a foot injury so it can be treated promptly. And get your feet checked by a podiatrist at least once a year.
Urinary Tract Infections
- Cloudy or bloody urine
- Foul-smelling urine
- Pain or burning when you urinate
- Low-grade fever
- Pressure or cramping in your lower abdomen or back
- Frequent urge to urinate, even after you use the bathroom
How to Prevent UTIs
- Stay hydrated. Drinking enough water dilutes bacteria in your urine and helps flush bacteria out.
- Urinate often. Holding it in gives infection-causing bacteria more time to grow.
- Practice good hygiene. Wipe from front to back, take showers instead of long baths, use tampons instead of pads, and pee after sex. All these things can help keep harmful bacteria out of your urinary tract.
- Wear breathable underwear. Breathable cotton is the name of the game. It helps reduce sweating, which in turn reduces harmful bacteria growth.
- Eat probiotic-rich foods. Think plain yogurt, miso soup, or fermented pickles. They help bolster your body’s community of good bacteria, which can help keep bad bacteria growth in check.
Skin Infections
Your skin is home to a vast number of nerves and blood vessels, and both can be damaged by high blood sugar.
“That, in turn, can raise your risk of bacterial or fungal skin infections,” Routhenstein says.
How to Prevent Skin Infections
- Wash your hands regularly with soap and water.
- Wash cuts with soap and water.
- Let your doctor know if you have signs of a possible skin infection.
Yeast Infections
These fungi normally live in and on our bodies in small amounts. But high blood sugar can make it easier for Candida to grow out of control and cause an infection.
“Elevated glucose creates a moist, sugar-rich environment that promotes yeast growth,” Routhenstein says.
- Itching and irritation
- Burning, especially during urination or sex
- Pain or soreness
- Redness and swelling
- Cottage cheese–like discharge
The earlier you begin to treat a yeast infection, the more effective the treatment is likely to be. If an infection doesn’t get better with over-the-counter treatments, or if it keeps coming back, it’s definitely time to see a doctor, who will be able to recommend and prescribe more powerful antifungal agents.
How to Prevent Yeast Infections
- Don’t use scented tampons, scented pads, or feminine deodorants.
- Avoid douching.
- Change out of wet or sweaty underwear or bathing suits quickly.
- Wear cotton underwear and loose-fitting bottoms.
- Choose water-based sexual lubricants.
Oral Infections
Diabetes can make you more prone to mouth and gum issues. As with other types of infections, high blood sugar can thwart healthy immune system functioning, reduce blood flow via damaged blood vessels, and provide more fuel for bacteria, all of which can lead to infections in your mouth.
- Gum disease: This harmful gum inflammation can make gums red, swollen, puffy, and prone to bleeding. Gingivitis is a common and mild form of the disease, which can result in periodontitis, a more serious form of gum disease, as well as tooth loss.
- Oral thrush: A fungal infection caused by candida overgrowth, oral thrush can cause dry mouth, discomfort, and white patches.
- Dry mouth: Dry mouth isn’t an infection, but it increases your risk of them. It can make your mouth uncomfortable and lead to tooth decay and fungal infections over time.
There are different treatments for different types of tooth and gum issues, so it’s important to see your dentist if you have concerning symptoms. Together, you can come up with a treatment plan based on your specific infection.
How to Prevent Oral Infections
- Brush your teeth twice daily with a fluoride toothpaste.
- Clean between your teeth once daily with dental floss, a dental pick, or another device recommended by your dentist.
- See your dentist regularly.
- Drink fluoridated water. Fluoride protects your teeth.
- Avoid smoking, or if you currently smoke, talk with your doctor about quitting.
Penis Foreskin Infections
Similar to how high blood sugar can increase the risk for fungal infections of the skin, it can also cause balanitis, or inflammation of the glans (or head) of the penis. The problem, which is often caused by a yeast infection, only affects uncircumcised men.
How to Prevent Penis Foreskin Infections
In addition to improved blood sugar control, lifestyle habits can reduce your risk of balanitis. You should bathe regularly, avoid harsh soaps, clean the area under your foreskin with warm water, and dry it completely. Always use a condom when having sex, since sexually transmitted infections can cause balanitis.
When to See a Doctor
Infections can quickly turn serious when you have diabetes. Folsom recommends contacting your primary care provider right away anytime you’re having infection symptoms. Those include redness, swelling, pain, or discharge around the site of the infection, or body-wide symptoms like fever, vomiting, or severe fatigue.
The Takeaway
- People with diabetes have a higher risk of developing a variety of infections, since chronically high blood sugar levels can compromise immune system response.
- Bacterial and fungal infections of the feet, skin, and mouth are more common in those with elevated blood glucose levels, as are urinary tract infections and yeast infections.
- To prevent escalating symptoms of infection or further complications, prompt medical attention is essential whenever symptoms of an infection are present, such as redness, pain, fever, or severe fatigue.
Resources We Trust
- Cleveland Clinic: Diabetes-Related Foot Conditions
- Mayo Clinic: Diabetic Neuropathy
- Centers for Disease Control and Prevention: Your Immune System and Diabetes
- Johns Hopkins Medicine: Anti-Inflammatory Diet
- Endocrine Society: Diabetes Complications
- Your Immune System and Diabetes. Centers for Disease Control and Prevention. May 15, 2024.
- Narres M et al. Incidence of lower extremity amputations in the diabetic compared with the non-diabetic population: A systematic review. PLoS One. August 28, 2017.
- Murphy-Lavoie HM et al. Diabetic Foot Infections. StatPearls. July 4, 2023.
- Diabetes-Related Foot Conditions. Cleveland Clinic. March 21, 2024.
- Tips for Healthy Feet. Centers for Disease Control and Prevention. May 15, 2024.
- Ahmed AE et al. Prevalence and Associated Risk Factors of Urinary Tract Infection among Diabetic Patients: A Cross-Sectional Study. Healthcare. March 15, 2023.
- Urinary Tract Infection — Adults. MedlinePlus. July 23, 2024.
- Treatment for Bladder Infection in Adults. National Institute of Diabetes and Digestive and Kidney Diseases. April 2024.
- Urinary Tract Infection Basics. Centers for Disease Control and Prevention. January 22, 2024.
- Rehmus WE. Overview of Bacterial Skin Infections. Merck Manual. June 2023.
- Diabetes and Your Skin. Centers for Disease Control and Prevention. May 15, 2023.
- Overview of Bacterial Skin Infections. Merck Manual. June 2023.
- Fungal Infections (Mycosis). Cleveland Clinic. October 25, 2022.
- Preventing and Treating Skin Infections. Centers for Disease Control and Prevention.
- O’Laughlin DJ et al. Diabetes and Vulvovaginal Conditions. Clinical Diabetes. March 27, 2024.
- Dave CV et al. Comparative risk of genital infections associated with SGLT2 inhibitors: A real-world retrospective cohort study. Diabetes, Obesity & Metabolism. October 11, 2018.
- Yeast Infection (Vaginal). Mayo Clinic. November 19, 2024.
- Vaginal Yeast Infection. Cleveland Clinic. September 2, 2022.
- Diabetes & Oral Health. National Institute of Dental and Craniofacial Research. October 2024.
- Dry Mouth. National Institute of Dental and Crankiofacial Research. October 2024.
- Oral Hygiene. National Institute of Dental and Craniofacial Research.
- Balanitis. Cleveland Clinic. January 30, 2023.

Anna L. Goldman, MD
Medical Reviewer
Anna L. Goldman, MD, is a board-certified endocrinologist. She teaches first year medical students at Harvard Medical School and practices general endocrinology in Boston.
Dr. Goldman attended college at Wesleyan University and then completed her residency at Icahn School of Medicine at Mount Sinai Hospital in New York City, where she was also a chief resident. She moved to Boston to do her fellowship in endocrinology at Brigham and Women's Hospital. She joined the faculty after graduation and served as the associate program director for the fellowship program for a number of years.
