Possibly, but only a little, and it hasn't been proven. A large Korean study found that people who brushed three or more times a day were about 8% less likely to develop diabetes over ten years than people who brushed less often. That is an association, not proof that brushing prevents diabetes. What is well established is that diabetes and gum disease affect each other, so caring for your gums matters more if you have diabetes or are at risk of it.
What did the study find?
Researchers at Ewha Womans University in Seoul used health records from 188,013 adults in Korea's national health screening program. None had diabetes at the start. The researchers looked at gum disease, the number of missing teeth and how often people said they brushed, then followed them for a median of ten years. About 16% developed diabetes. [1]
After adjusting for age, exercise, smoking, alcohol and other health factors:
Brushing three or more times a day was linked to about 8% lower diabetes risk.
Gum disease was linked to about 9% higher risk.
Missing 15 or more teeth was linked to about 21% higher risk. [1]
What are the limits?
It is observational. People who brush more often may also eat better, exercise more or see doctors more, and not all of that can be adjusted for.
Brushing was self-reported, at a single point in time.
The study was in Korea, and results may differ in other populations.
The effect is small. Weight, physical activity and diet remain the main things you can change to lower type 2 diabetes risk.
The authors concluded that better oral hygiene "may be associated" with lower diabetes risk, and that more research is needed. [1]
How are gum disease and diabetes connected?
This part is not in doubt. People with diabetes are more likely to develop gum disease, and it tends to be more severe, especially when blood sugar runs high. Severe gum disease, in turn, can make blood sugar harder to control. [2] Researchers think long-term inflammation from infected gums is part of the reason.
What should you do?
Brush twice a day with fluoride toothpaste and clean between your teeth daily. Brushing after meals is reasonable if you want to brush more often.
Keep your blood sugar in your target range if you have diabetes.
Tell your dentist if you have diabetes or prediabetes, and tell your physician if you have gum disease.
Watch for bleeding, swollen or receding gums. These are signs to see a dentist.
If you have diabetes and your mouth feels dry, our post on how to stop dry mouth caused by diabetes has practical steps. For other connections between your gums and your health, see can gum disease affect your overall health?
Where can you have your gums checked in Jacksonville?
A comprehensive dental exam at our office includes a full gum evaluation and a review of your medical history. Contact us or call 904-398-1549.
Sources
Chang Y, Lee JS, Lee KJ, Woo HG, Song TJ. Improved oral hygiene is associated with decreased risk of new-onset diabetes: a nationwide population-based cohort study. Diabetologia. 2020;63(5):924-933. doi:10.1007/s00125-020-05112-9 (retrieved via PubMed)
National Institute of Diabetes and Digestive and Kidney Diseases. Diabetes, gum disease and other dental problems.
About the author. CJ Henley, DMD, is a general dentist in Jacksonville whose practice focuses on cosmetic and restorative dentistry, dental implants and dental care around head and neck cancer. Meet Dr. Henley.
CJ Henley, DMD, PA · 3675 Hendricks Avenue, Jacksonville, FL 32207 · 904-398-1549
Updated October 2026.