Are you someone who worries, "I'm doing my best with diet and exercise to control my blood sugar, but maybe it's still not enough?" Then, are you brushing your teeth properly?
For those in their 40s and older who are starting to worry about their health, diabetes and periodontal disease are both common concerns. Although diabetes and periodontal disease may seem unrelated, it is known that they are closely connected in a "bidirectional vicious cycle." Not only are people with periodontal disease more likely to develop diabetes, but it has also been suggested that treating periodontal disease in people with diabetes may improve their blood sugar levels.
This article explains the inseparable relationship between diabetes and periodontal disease, and highlights the importance of oral care, which is also helpful in controlling blood sugar levels.
table of contents
Diabetes and periodontal disease: The vicious cycle in both directions
Diabetes and periodontal disease have a reciprocal relationship, negatively impacting each other. Let's examine this from two perspectives: specifically, the mechanism by which diabetes worsens periodontal disease, and conversely, the mechanism by which periodontal disease worsens diabetes.
Mechanism 1: Diabetes worsens periodontal disease.
People with type 1 diabetes have a higher incidence of periodontal disease compared to healthy individuals, and even among people with type 2 diabetes, those with an HbA1c level of 6.5% or higher are at increased risk of developing periodontitis and the loss of alveolar bone (the bone that supports the teeth).
The main cause is high blood sugar itself, but more specifically, it is as follows:
- The proportion of bacteria that prefer sugar increases.
- This results in dysfunction of neutrophils' migratory, phagocytic, and bactericidal functions.
- Advanced glycation end products (AGEs) produced by high blood sugar levels alter and weaken functional matrix components of periodontal tissue, such as collagen and laminin.
- High blood sugar levels can lead to dehydration, making the mouth more prone to dryness, impairing the self-cleaning action of saliva, and increasing the likelihood of inflammation.
High blood sugar levels negatively impact both the oral environment and the body's defense systems by creating an environment where periodontal bacteria can easily multiply, and by making it difficult to control infections.
Source: Diabetes Treatment Guidelines 2024 | Chapter 16 Diabetes and Periodontal Disease
Mechanism 2: Periodontal disease worsens blood sugar levels.
Conversely, there is also a mechanism by which periodontal disease can worsen diabetes. If severe periodontal disease is left untreated, blood glucose control (HbA1c) may worsen. A study that tracked 2,973 non-diabetic patients in the Pomerania region of Germany found a significant correlation between the severity of periodontal disease and the worsening of HbA1c. The association was particularly pronounced in people with high levels of high-sensitivity CRP, an indicator of inflammation in the body.
This is thought to be because periodontal disease is a "mild chronic inflammatory disease." It is hypothesized that inflammatory substances (such as cytokines) generated in the gums due to periodontal disease enter the bloodstream and circulate throughout the body, interfering with the function of insulin (insulin resistance), and consequently worsening the ability to lower blood sugar levels (glucose tolerance).
Source: Diabetes Treatment Guidelines 2024 | Chapter 16 Diabetes and Periodontal Disease Source: Periodontal Status and A1C Change: SHIP Study (Diabetes Care (2010))
Periodontal disease treatment improves blood sugar control.
The "bidirectional vicious cycle" between diabetes and periodontal disease means, conversely, that "treating periodontal disease can be expected to have a positive impact on blood sugar levels." In fact, the Japan Diabetes Society guidelines recommend periodontal treatment for type 2 diabetes patients as "grade A (strongly recommended)" because it is effective in improving blood sugar control.
It is believed that treating periodontal disease and stopping gum inflammation reduces inflammatory substances that interfere with insulin function, resulting in improved insulin resistance and better blood sugar control. A meta-analysis of multiple studies showed that periodontal disease treatment resulted in a statistically significant 0.36% improvement in HbA1c.
Not all studies agree on this point. However, there are several reports indicating that periodontal treatment is effective in improving HbA1c levels, suggesting that periodontal treatment is beneficial for some patients.
Source: Diabetes Treatment Guidelines 2024 | Chapter 16 Diabetes and Periodontal Disease Source: Japanese Society of Periodontology | Periodontal Treatment Guidelines Revised 2nd Edition 2014
Oral care for diabetic patients | Practical guide
What specifically should people with diabetes (or those at risk) do to break the vicious cycle of diabetes and periodontal disease?
The key is to balance "self-care" and "professional care."
- Regular dental checkups
- Proper daily brushing using dental floss and interdental brushes
- A balanced diet and moderate exercise
People with diabetes are at higher risk of periodontal disease, so it is recommended that they have a dental checkup every six months, even if they have no symptoms. Get professional cleaning to help with early detection and treatment of the disease.
Using fluoride toothpaste and brushing your teeth carefully is fundamental to self-care. It's especially important to care for the spaces between your teeth, where plaque is difficult to remove with a toothbrush alone. Always use dental floss or interdental brushes in conjunction with brushing to thoroughly remove plaque.
A balanced diet and moderate exercise are important not only for controlling blood sugar levels but also for preventing periodontal disease.
summary
Diabetes and periodontal disease have a "two-way relationship" where they negatively impact each other. Blood sugar control by an internal medicine doctor and oral care by a dentist are both insufficient on their own. They are like "two wheels of a car," and it is important to advance both simultaneously. Consider "gum health" as an important part of blood sugar control, and why not reconsider your dental care starting today?
Supervised by: Yuzo Terakawa, M.D. (Board-certified neurosurgeon)
