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Diabetes and Your Teeth and Gums

Diabetes raises the risk of gum disease, and gum disease can make blood glucose harder to control. Here is how diabetes affects the mouth, how to protect it, and what to tell your dentist.

Updated September 2026·By the OHA editorial team·7 min read·How we write
Key takeaways
  • People with diabetes are more likely to get gum disease, especially when blood glucose is often above the target range. The link runs both ways: gum disease may make blood glucose harder to control.
  • Diabetes can also bring a dry mouth, tooth decay, oral thrush (a fungal infection), slower healing and changes in taste.
  • Keeping blood glucose in your target range, brushing twice a day with fluoride toothpaste, cleaning between your teeth daily and not smoking all help.
  • Tell your dentist you have diabetes, how well it is controlled and what medicines you take, and ask how often you should have a check-up.
  • A Cochrane review found moderate-certainty evidence that treating gum disease modestly improves blood glucose for some months.

The US National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) says people with diabetes are more likely to have gum disease, cavities and other problems with their teeth and gums, and that some of these problems can make diabetes worse. The NHS lists gum disease among the long-term complications of type 2 diabetes. The encouraging part is that much of this can be prevented.

How are diabetes and gum disease linked?

Gum disease is inflammation of the gums and the bone that hold your teeth in place. It starts as gingivitis (red, swollen gums that may bleed) and can progress to periodontitis, which damages the bone around the teeth and can lead to tooth loss. NIDDK describes gum disease as the most common and serious mouth problem related to diabetes.

Diabetes raises the risk of gum disease

The US National Institute of Dental and Craniofacial Research (NIDCR) says people with poor blood glucose control get gum disease more often and more severely than people whose diabetes is well controlled. The Australian Dental Association says people whose blood glucose is well managed have the same risk of periodontitis as people without diabetes.

Health bodies give several reasons:

  • Lower resistance to infection. The Better Health Channel (Victoria) says people with blood glucose above the target range generally resist infection and heal less well. The US Centers for Disease Control and Prevention (CDC) says high blood glucose weakens white blood cells, the body's main defence against infections in the mouth.
  • More glucose in saliva. NIDDK explains that this feeds the bacteria that form plaque (the sticky film on teeth), which can harden into tartar near the gumline and cause gum disease.
  • Less saliva. NIDDK says diabetes and some diabetes medicines can reduce saliva, raising the risk of cavities and gum disease.

Gum disease may make diabetes harder to control

NIDCR says having gum disease may make your blood sugar harder to control, and the CDC says the same. The Australian Dental Association describes evidence of a two-way relationship: people with periodontitis have a higher HbA1c (a blood test reflecting your average blood glucose over about three months) and a higher chance of developing prediabetes and diabetes. It adds that these relationships can differ between type 1 and type 2 diabetes.

What other mouth problems can diabetes cause?

The Australian Dental Association, the Better Health Channel, NIDCR and NIDDK list:

  • Dry mouth. NIDCR says a lack of saliva can cause soreness, ulcers, infections and tooth decay. See dry mouth.
  • Tooth decay. The Better Health Channel says extra glucose in saliva and a dry mouth let plaque build up, and that decay can start on tooth roots exposed when gums shrink back. See tooth decay.
  • Oral thrush. A fungal infection that can cause white patches in the mouth. The Better Health Channel says a dentist can prescribe antifungal medicine if needed. See oral thrush.
  • Slow healing. NIDCR says diabetes can slow healing, which can interfere with gum treatment.
  • Changes in taste. The Better Health Channel says the cause is not clear.
  • Burning mouth. NIDDK lists a burning feeling inside the mouth, which it links to uncontrolled blood glucose.

The Better Health Channel notes that the first signs of diabetes can appear in the mouth, and NIDDK calls dry mouth an important sign of diabetes.

How can you look after your mouth?

The Better Health Channel, the Australian Dental Association, NIDCR and NIDDK advise:

  1. Keep your blood glucose as close to your target range as you can. NIDCR says this is key to controlling and preventing mouth problems.
  2. Brush twice a day with fluoride toothpaste and a soft toothbrush, gently where the gums meet the teeth. See how to brush your teeth.
  3. Clean between your teeth once a day with floss or interdental brushes. See cleaning between your teeth.
  4. Avoid a dry mouth. The Better Health Channel suggests drinking plenty of water and chewing sugar-free gum.
  5. Do not smoke. The Better Health Channel says smoking raises the risk of gum disease whether or not you have diabetes, and quitting helps healing after gum treatment. See smoking, vaping and oral health.
  6. If you wear dentures, NIDCR says to tell your dentist if they do not fit well or your gums are sore.

The Better Health Channel says it is a myth that gum disease is an unavoidable part of diabetes: good oral hygiene and well-controlled blood glucose greatly reduce the risk.

What should you tell your dentist?

NIDDK says to tell your dentist how long you have had diabetes, any diabetes-related problems and the medicines you take, and to keep them updated, including about rises in your blood glucose. The Australian Dental Association says to include over-the-counter medicines.

Before oral surgery or other extensive dental work, NIDDK says high blood glucose increases the risk of infection afterwards and can slow healing. It advises asking your doctor how often to check your blood glucose around the procedure and whether any medicines need adjusting.

How often should you have a check-up?

All the bodies we checked say regular dental visits matter if you have diabetes. They differ on how specific they are.

  • UK: the NHS advises regular dental check-ups, especially if you have type 2 diabetes. NHS inform (Scotland) says that people at higher risk of gum problems, for example because of diabetes, may be advised to visit more often.
  • Australia: the Better Health Channel advises visiting your dentist every 6 to 12 months. The Australian Dental Association says your dentist will tell you how often, and you may need to go more often if diabetes has caused problems in your mouth.
  • US: the CDC, NIDDK and the American Dental Association (ADA) all say to ask your dentist how often you should come in.

See dental check-ups for what happens at a visit.

Does treating gum disease improve blood glucose?

The sources differ in how confident they are.

  • A 2022 Cochrane review of 35 trials found moderate-certainty evidence that deep cleaning below the gumline lowered HbA1c by an average of 0.43 percentage points at 3 to 4 months, with a smaller difference at 6 months and a single study showing a benefit at 12 months. Almost all participants had type 2 diabetes, and there were not enough studies to judge side effects.
  • The Australian Dental Association says treatment has shown a mild improvement that lasted only three months, with longer-term studies under way.
  • The Better Health Channel, the ADA and the CDC say treating gum disease may help improve blood glucose.

In short: there is reasonable evidence of a modest benefit over a few months, mainly for type 2 diabetes. How long it lasts is less certain. The Australian Dental Association's advice is to look after both your oral health and your diabetes.

When to see a dentist
  • Your gums are red, swollen, tender or bleed when you brush or clean between your teeth.
  • Your gums are shrinking back, your teeth feel loose, or gaps are opening up between them.
  • You have a dry mouth, white patches, soreness, or bad breath that does not go away.
  • Your dentures no longer fit well.
Get help urgently
  • The NHS says to ask for an urgent dental appointment if you have gum disease with very sore and swollen gums, teeth becoming loose or falling out, or ulcers or red patches in your mouth. The Better Health Channel says to see your dentist immediately if pus is coming from your gums.
  • A swollen face or jaw, intense pain or a high temperature may be a dental abscess. Call 999 or go to A&E (or your local emergency number) if you are finding it hard to breathe, speak, swallow or open your mouth, or have a lot of swelling in your mouth (NHS advice).

Frequently asked questions

Is gum disease inevitable if I have diabetes?

No. The Better Health Channel says this is a myth, and the Australian Dental Association says people whose blood glucose is well managed have the same risk of periodontitis as people without diabetes.

Does it matter whether I have type 1 or type 2 diabetes?

The Australian Dental Association says the relationship with gum disease can differ between the two, and the Cochrane review of gum treatment was based almost entirely on people with type 2 diabetes.

What about fast-acting sugary foods and drinks?

After fast-acting carbohydrates such as jellybeans, soft drink or fruit juice, the Australian Dental Association suggests drinking water to rinse sugar and acid away, and waiting 60 minutes before brushing. See sugar, acid and your teeth.

Sources

  1. Diabetes, Australian Dental Association, accessed September 2026
  2. Diabetes and oral health, Better Health Channel (Victoria), accessed September 2026
  3. Diabetes, gum disease, and other dental problems, NIH National Institute of Diabetes and Digestive and Kidney Diseases, accessed September 2026
  4. Diabetes and oral health, NIH National Institute of Dental and Craniofacial Research, accessed September 2026
  5. Diabetes and oral health, Centers for Disease Control and Prevention, accessed September 2026
  6. Diabetes and dental health, American Dental Association (MouthHealthy), accessed September 2026
  7. Gum disease, NHS, accessed September 2026
  8. Complications of type 2 diabetes, NHS, accessed September 2026
  9. Dental abscess, NHS, accessed September 2026
  10. Gum disease, NHS inform (Scotland), accessed September 2026
  11. Does treatment for gum disease help people with diabetes control blood sugar levels?, Cochrane (Simpson and others, 2022), accessed September 2026

This article is general information about oral health. It is not a diagnosis or a substitute for advice from a dentist or doctor who knows your situation. If you have pain, swelling, bleeding that does not settle, or a problem that is getting worse, see a dental professional. In an emergency, contact your local emergency service.

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