The surprising link between chewing and type 2 diabetes

A recent study found that type 2 diabetic patients with full chewing function have significantly lower blood sugar levels than patients with reduced chewing ability. The research reveals that chewing stimulates processes that contribute to reduced blood sugar levels and therefore suggests the importance of oral health in diabetes management.

Mehmet A. Eskan, a researcher at the University at Buffalo, has a recommendation for doctors treating people with type 2 diabetes (T2D): Check your patients’ teeth.

Eskan’s recent research, published in the journal PLOS ONE, revealed a remarkable correlation between chewing functionality and blood sugar levels in T2D patients. Specifically, he found that patients with T2D who maintain full chewing ability exhibit significantly lower blood glucose levels compared to those with compromised masticatory function. Eskan is a clinical assistant professor at the Department of Periodontology and Endodontics at the School of Dental Medicine at University at Buffalo.

The retrospective study looked at data collected 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 positioned correctly and in contact in such a way that a person can chew their food well. This group’s blood sugar level was 7.48. The other group could not chew well, if at all, because they were missing some or all of these teeth; their blood sugar level was almost 2% higher, at 9.42.

Chewing matters

When you sit down at a picnic table with family and friends, chewing – chewing – is the last thing on your mind. But as you bite into your burger, several things begin to happen. Digestion, the process by which your body extracts nutrients from food, begins when chewing stimulates the production of saliva. Nutrients important for reducing blood sugar levels include fiber, which is largely obtained by chewing appropriate foods. Chewing has also been reported to stimulate reactions in the gut that lead to increased insulin secretion and the hypothalamus, which promotes a feeling of satiety, resulting in less food intake. Eating less reduces 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 Ph.D. at the University of Louisville, where he also completed a periodontology residency. “My particular clinical interest is treating dental patients who are systemically compromised,” he said. His research goal is to contribute to the big picture of improving public health. This research notes that as of 2019, nearly half a billion people worldwide had diabetes, and at least 90% of those patients with diabetes have T2D.

Oral health management 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 that there is a strong association between chewing and control of blood sugar levels among T2D patients,” Eskan said. This study did not find any independent variables that could influence blood glucose levels among subjects because there were no statistical differences among subjects in terms of body mass index (BMI), sex, smoking status, medication, or infection as indicated by white blood cell (WBC) count at baseline .

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

Complications kill

Research has shown that an increase of just 1% in blood sugar levels is associated with a 40% increase in mortality from cardiovascular or ischemic heart disease among people with diabetes, according to Eskan. Other complications can include kidney disease, eye damage, neuropathy, and slow healing of simple wounds such as ulcers and blisters.

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

Reference: “Masticatory inefficiency due to decreased or lack of occlusal support is associated with increased blood glucose levels in patients with type 2 diabetes” by Yeter E. Bayram and Mehmet A. Eskan, April 14, 2023, PLUS ONE.
DOI: 10.1371/journal.pone.0284319