After 31 years of practice, I have seen a correlation between my patients with higher numbers of missing teeth and their failing health. Research largely bears my observations out. Today I am going to discuss five papers that give a little more clarity to the subject of dental health as it relates to overall health and mortality.

Study I

In 2015, Hsiao-Yun Hu and colleagues looked at over 55,000 people to determine how the number of teeth they had related to their mortality. They also included body mass index (BMI). The rationale for their study rests on two observations in the literature; the first is that tooth loss is linked to cardiovascular disease, stroke, and dementia. The second is that tooth loss is associated with obesity in numerous studies. As expected, participants with no teeth exhibited a higher mortality rate (12.53%) than did those with 10 to 19 teeth (8.01%) and those with 20 teeth or more (5.74%). A significant positive correlation of body mass index (BMI) with all-cause mortality occurred in both underweight and overweight elderly patients. They attribute the higher mortality for underweight patients to loss of chewing ability, which leads to an inability to eat certain nutritious foods and the higher mortality among obese patients eating more refined (less healthy) foods. (1)

Study II

In 2019 Juxiang Peng and associates reviewed 18 previous studies and concluded that the relationship between tooth loss and susceptibility to all-cause mortality is measurable. They claim the association is because tooth loss represents a lifetime of poor oral hygiene that leads to oral infections that are associated with multiple adverse health effects, including epilepsy, cognitive impairment, ischemic heart disease, heart failure, stroke, peripheral vascular diseases, and cancer. (2)

Study III

A paper from 2000 by Freidman and Lamster looked at centenarians and found that they had more teeth compared to those who died younger. (3)

Study IV

A French study from 2017 by Adolph, Darneaud et al. looked at all-cause mortality and tooth loss like the previous studies I cited today, but they also looked at a few other variables including dental plaque, dental calculus, gingival inflammation, tooth loss, and the number of teeth that occluded with each other. They found increased all-cause mortality with higher plaque, gingival inflammation, greater numbers of missing teeth, and fewer teeth that occluded with each other. The mortality went up as the subjects were exposed to any two of the factors, and peeked with three or more exposures. See their graph below for details. They attribute their findings to the oral bacteria entering the body, and their tendency to increase blood mediators of inflammation. (4) For more on the subject, you can read my post on it here.

Study V

One last study by Paganini-Hill and others looked at missing teeth and mortality and found a strong correlation. They also looked at oral hygiene habits and how that contributed to mortality. Not surprisingly, they found a 20-35% increased risk factor for all-cause mortality for those who did not brush at night, a 30% increase in risk for those who never flossed, and a 30-50% increase in the death rate for those who had not seen a dentist in the last 12 months! (5)

Tooth decay and gum disease are almost exclusively caused by poor diet and smoking. You don’t have to be a medical researcher to understand that poor dietary habits and smoking may lead to poorer health and earlier death. Oral infections lead to systemic inflammation associated with obesity, diabetes, cancer, heart disease, Alzheimer’s disease, and more, which can shorten lives considerably.

 Underlying illnesses aside, missing teeth lead to malnourishment for two main reasons. The first is that if certain foods can’t be adequately masticated, then they may be avoided along with the vital nutrients they contain. The second reason is that chewing of whole foods like nuts and seafood becomes impossible, so highly processed, high carbohydrate foods may likely be substituted. Subjects with replacement teeth can chew better and therefore have lower all-cause mortality rates, so all is not lost for those who have already lost teeth. When your dentist suggests replacing a missing tooth, consider the positive benefits to your longevity.