Frequent toothbrushing found to lower risk of diabetes
SEOUL, South Korea: A recent study has highlighted the importance of good dental hygiene. Since periodontal disease and poor oral hygiene can provoke transient infection and systemic inflammation, researchers have examined the effect that periodontal disease and poor oral hygiene have on the occurrence of new-onset diabetes. They found that frequent toothbrushing may reduce the chances of developing diabetes, while the presence of periodontal disease and more missing teeth increase the chances of developing new-onset diabetes.
According to the World Health Organization, over 400 million people worldwide have diabetes and diabetes was the seventh leading cause of death in 2016. Inflammation plays a key role in the onset of diabetes. Dental Tribune International has reported on a study that linked previously undetected diabetes and impaired glucose tolerance to myocardial infarction and severe periodontitis.
In the present study, the researchers analysed data from the National Health Insurance Service—Health Screening Cohort in South Korea collected between 2003 and 2006. The sample included 188,013 subjects who were examined on their oral hygiene behaviours and the number of missing teeth.
The study found that 17.5% of the subjects had periodontal disease, and diabetes was diagnosed in 31,545 of the participants (16%) at a ten-year follow-up. After adjusting for certain oral health-related factors, the presence of periodontal disease and 15 or more missing teeth were both linked to increased risk of developing diabetes by 9% and 21%, respectively. Brushing the teeth three times per day or more was associated with an 8% decreased risk of developing diabetes.
Further analysis revealed that adults aged 51 years and under who brushed their teeth twice a day reduced their risk of developing diabetes by 10%, and those who brushed their teeth three times a day, by 14%, compared with those who brushed once a day or did not brush at all. Adults aged 52 years and older did not experience any difference in diabetes risk in the study when brushing once or twice a day or not at all. However, the researchers found that brushing three or more times per day, compared with once or not at all, was associated with a 7% decreased risk.
Additionally, periodontal disease appeared to have a stronger effect in younger adults and was associated with a 14% increased risk of developing diabetes, while the increased risk was 6% in the older group. Adults aged 51 years and under who had one to seven missing teeth were found to have a 16% increased risk of diabetes, whereas those who were 52 years and above and had 15 or more missing teeth increased their chances of developing diabetes by 34%.
The researchers also noted certain differences between men and women in the study. Women who brushed their teeth twice or more per day experienced a 15% and 8% reduction of developing diabetes, respectively, when compared with women who brushed once a day or not at all. For men, there was only a 5% reduction in risk of diabetes for those who brushed three times or more per day, compared with those who brushed once a day or not at all. There was no statistically significant difference in risk between men who brushed twice a day and those who brushed once a day or not at all.
The authors believe that, while the study does not explain the connection between oral hygiene and the development of diabetes, dental caries may contribute to chronic and systemic inflammation and increase the production and circulation of inflammatory biomarkers. These markers have previously been shown to be linked with insulin resistance and the development of diabetes.
“Frequent toothbrushing may decrease the risk of new-onset diabetes, and the presence of periodontal disease and increased number of missing teeth may increase that risk. Overall, improving oral hygiene may be associated with a decreased risk of occurrence of new-onset diabetes,” the researchers concluded.
The study, titled “Improved oral hygiene is associated with decreased risk of new-onset diabetes: a nationwide population-based cohort study”, was published online on 2 March 2020 in Diabetologia, ahead of inclusion in an issue.