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Ability to chew properly linked to blood sugar levels in patients with Type 2 diabetes

X-ray of a mouth with many dental implants.

A post-operative panoramic X-ray shows fixed implant-supported restoration. Image: University at Buffalo.


Published May 10, 2023

Mehmet A. Eskan.
“My special clinical interest is to treat dental patients who are systemically compromised. I’m interested in research that can improve people’s health now. ”
Mehmet A. Eskan, clinical assistant professor
Department of Periodontics and Endodontics

If you’re a health care provider treating people with Type 2 diabetes (T2D), UB researcher Mehmet A. Eskan has this suggestion for you: check your patients’ teeth.

In a study published April 14 in PLOS ONE, Eskan, clinical assistant professor in the Department of Periodontics and Endodontics, School of Dental Medicine, demonstrates that patients with T2D who have full chewing function have a blood glucose level that is significantly lower than patients whose ability to chew effectively is impaired.

The retrospective study looked at data gathered from 94 patients with T2D who had been seen at an outpatient clinic in a hospital in Istanbul, Turkey. The patients were divided into two groups. The first group included patients who had good “occlusal function” — enough teeth placed properly and making contact in such a way that a person can chew their food well. That group’s blood glucose level was 7.48. The second group couldn’t chew well, if at all, because they were lacking some or all of those teeth; their blood glucose level was almost 2% higher, at 9.42.

Mastication matters

When you sit down at a picnic table with family and friends, mastication — chewing — is the last thing on your mind. However, as you bite into your burger, several things start to happen. Digestion, the process by which your body extracts nutrients from food, begins as chewing stimulates the production of saliva. Nutrients that are important to reducing blood glucose levels include fiber, which is obtained in large part through chewing appropriate foods. Chewing also has been reported to stimulate reactions in the intestine that lead to increased insulin secretion, and in the hypothalamus that promote a feeling of satiety, resulting in less food intake. Eating less decreases the likelihood of becoming overweight, which is a major risk factor for developing T2D.

Dental care and the big picture

Eskan received his DDS at Hacettepe University, a leading medical research center in Turkey, and earned his PhD at the University of Louisville, where he also completed a residency in periodontology. “My special clinical interest is to treat dental patients who are systemically compromised,” he explains. His research goal is to contribute to the big picture of improving public health. This research notes that, as of 2019, almost half a billion people worldwide had diabetes, and at least 90% of those patients with diabetes have T2D.

Addressing oral health has recently become part of the approach to managing diabetes, along with encouraging patients to maintain a healthy weight, eat a healthy diet and quit smoking. “Our findings show there is a strong association between mastication and controlling blood glucose levels among T2D patients,” Eskan says. This study did not find any independent variables that could affect blood glucose levels among the subjects because there were no statistical differences among subjects regarding body mass index (BMI), sex, smoking status, medications or infection as indicated by white blood cell count (WBC) at baseline.

The dramatic improvement in one patient’s case described in a 2020 study co-led by Eskan illustrates the potential benefit of improving occlusal function through dental implants and appropriate fixed restoration. A T2D patient whose chewing function was severely impaired by missing teeth presented initially with a blood glucose level of 9.1. The patient obtained nutrition by using a bottle and eating baby food. Four months after treatment with a full-mouth implant-supported fixed restoration, the patient’s glucose level dropped to 7.8. After 18 months, it decreased to 6.2.

Complications kill

Research has shown that an increase of just 1% in blood glucose level is associated with a 40% increase in cardiovascular or ischemic heart disease mortality among people with diabetes, Eskan notes. Other complications can include kidney disease, eye damage, neuropathy and slow healing of simple wounds like cuts and blisters.

“I’m interested in research that can improve people’s health now,” Eskan says. He and co-author Yeter E. Bayram of the Department of Internal Medicine, Hamidiye Sisli Etfal Education and Research Hospital, Istanbul, look forward to further studies that explore possible causal relationships between occlusal support and blood glucose levels.


As someone with diabetes, I am grateful for this research, as it sheds light on the important connection between oral health and blood glucose control. This information empowers me to take proactive steps to improve my oral health and chewing function for my diabetes management.

By understanding the link between chewing, nutrient absorption, insulin secretion and satiety, health care providers can help patients make informed dietary choices that support healthy blood glucose levels.

Stephanie Nath