The risk of developing pancreatic cancer was 63 percent higher in
smokers who had lost all their teeth, compared with those who had
lost fewer than 10 teeth, researchers reported in the American
Journal of Clinical Nutrition (news
- web
sites). Overall, the risk of pancreatic cancer in the group was
about 6 in 1000.
The study doesn't show that tooth loss causes pancreatic cancer,
the study's lead author Rachel Z. Stolzenberg-Solomon said in an
interview with Reuters Health.
Tooth loss could simply be a marker for some other factor that
leads to cancer, said Stolzenberg-Solomon, an investigator in the
Nutritional Epidemiology Branch at the National Cancer Institute (news
- web
sites). For example, she said, tooth loss could simply be a
marker for an unhealthy lifestyle.
On the other hand, Stolzenberg-Solomon said, smokers who have
lost all their teeth may have more bacteria in their mouths. And
this higher level of bacteria in the mouth may lead to higher levels
of bacteria in the gut.
"There is a hypothesis that connects bacterial load with
pancreatic cancer," Stolzenberg-Solomon said. "Bacteria in the
stomach convert nitrates and nitrites into nitrosamines. And
nitrosamines are carcinogens."
For the new study, Stolzenberg-Solomon and her colleagues
examined the medical records of 29,104 male smokers. The men, who
were aged 50 to 69 at the start of the study, were followed from
1985 to 1997. They were asked about their dental health at the
beginning of the study. By the end of the study, 174 men had
developed pancreatic cancer.
After taking age, education, and whether the men lived in a rural
or urban environment into account, the researchers found that men
were 63 percent more likely to develop pancreatic cancer if they had
lost all their teeth.
While the new study doesn't prove that the conditions that
promote tooth loss lead to an elevated cancer risk, it does
underscore the importance of good dental hygiene,
Stolzenberg-Solomon said.
Studies have shown that the use of dental floss and toothpaste
are linked with lower risk of cancers of the mouth and esophagus,
she said.
Source: American Journal of Clinical Nutrition 2003;78:176-181.
