Link between tooth loss and increased risk of obesity discovered

An analysis of medical records of 1,765 older adults showed that patients with at least 21 teeth were more likely to maintain a healthy body weight than those with fewer teeth.

Each additional missing tooth is associated with a 2% increase in the likelihood of obesity, while each missing pair of opposing molars is associated with a 7% increase in the likelihood of obesity.

“Many healthy foods, especially raw fruits and vegetables, are difficult to eat when you lack functional teeth,” said Rena Zelig, an assistant professor at the Rutgers School of Health Professions and lead author of the study published in the journal Gerodontology. “One possible explanation is that when people, especially older adults, lose their teeth and have difficulty chewing, they start eating foods that are easier to eat but less healthy, such as mashed potatoes, cookies or cake. These foods are typically higher in calories, fat and sugar, which can lead to weight gain.”

The researchers examined data on 1,765 adults aged 65 to 89 who underwent treatment at Rutgers School of Dental Medicine between 2016 and 2022.

To analyze the relationship between the number of teeth and body mass index (BMI), they used statistical methods that took into account other factors that can affect BMI, such as age, gender, and current health conditions.

Approximately 73% of participants were either overweight or obese. The average number of remaining teeth was 20, just below the minimum requirement for functional chewing of 21, although 45% of participants had at least 21 teeth. (A complete set usually contains 32 teeth, including wisdom teeth.)

Unlike the back teeth (molars), which are more important for chewing, the front teeth are generally used for biting food and do not appear to affect weight status as significantly as the molars do. There was no significant association between the number of pairs of front teeth (which are usually lost after the molars) and BMI.

These results are consistent with previous studies indicating that poor dental health is linked to weight problems. However, this study uniquely highlights the important role of molars in maintaining a healthy weight.

Poor dental health has also been linked to other health problems, including oral and other cancers, as well as cardiovascular disease and diabetes.