Periodontal disease and pancreatic cancer
An intriguing article appeared in the Journal of the National Cancer Institute showing a correlation between periodontal disease and the development of pancreatic cancer. There have been a couple of studies correlating tooth loss with pancreatic cancer, but this is the first study I’ve seen that looks at periodontal disease and cancer of the pancreas.
You don’t want to get any kind of cancer if you can help it, but you really don’t want to get cancer in your pancreas. The virulence of cancers are usually defined by their 5-year survival rates, meaning what percentage of people who are diagnosed with a particular cancer are still alive 5 years later. The lower the 5-year survival rate, the deadlier the cancer. According to the latest statistics from the American Cancer Society (ACS), breast cancer has a 5-year survival rate of 88.5 percent, which means that out of 100 patients who are diagnosed with breast cancer, 88.5 of them will still be alive 5 years later. For lung cancer, a pretty deadly cancer, the 5-year survival rate is 15 percent. The 5-year survival rate for pancreatic cancer is 5 percent, making it the most deadly of all the cancers listed in the ACS list. Pancreatic cancer is a good one to avoid.
According to most papers I’ve read the only established modifiable risk factor for pancreatic cancer is smoking. There is evidence is starting to accumulate suggesting that diabetes, obesity and insulin resistance are also associated with increased risk. Recently a number of papers have been published showing that sugar, sugar-sweetened beverages, and high-glycemic-load diets are associated with an increased risk for this deadly cancer.
Now comes this paper showing that male health professionals with periodontal disease have significantly higher rates of pancreatic cancer. And the more severe the periodontal disease, the higher the correlation. Why should periodontal disease predispose to pancreatic cancer? I think the reason is pretty obvious, but the authors of the paper dance all around the issue.
According to the authors
Several mechanisms could potentially explain the observations from this study. Inflammation appears to play an important role in pancreatic cancer pathogenesis, although the inflammatory mediators that lead to the development of pancreatic cancer remain poorly defined. An association between periodontal disease and systemic inflammation has been observed using biomarkers. In the HPFS [Health Professionals Follow-Up Study, the study from which the database for this analysis was drawn], plasma C-reactive protein levels were 30% higher in individuals with a history of periodontal disease than in those with no history. We hypothesize that periodontal disease may promote pancreatic carcinogenesis through inflammation.
Alternatively, periodontal disease could influence pancreatic carcinogenesis through increased generation of carcinogens, namely nitrosamines. Individuals with periodontal disease and poor oral hygiene have elevated levels of oral bacteria and have much higher nitrosamine levels in their oral cavity due to nitrate-reducing bacteria. Nitrosamines and gastric acidity have been hypothesized to have an important role in pancreatic cancer; numerous studies support this hypothesis [I found only one].
To summarize, the authors hypothesize that the inflammation caused by the infection in the gums causes the pancreatic cancer and/or the increased gastric acidity from the nitrosamines produced by action of the infectious bacteria.
I suppose that inflammation and increased gastric acidity could cause it, but I don’t believe those are the most likely causes. Remember, we’ve got a number of studies showing that the consumption of sweets and a high-glycemic diet appears to increase the risk for pancreatic cancer. There is evidence that obesity, diabetes and insulin resistance are correlated with increased rates of pancreatic cancer. And now we’ve got periodontal disease to add to the mix.
What causes periodontal disease? I’ll give you a clue. Just as with dental caries (cavities), periodontal disease doesn’t appear in the remains of pre-agricultural man. Periodontal disease is easily recognizable from skeletal remains, and it just ain’t there in our meat-eating ancestors. Once agriculture took root (no pun intended), dental caries and periodontal disease became common. It’s hard to find an ancient Egyptian mummy without severe dental disease. And remember, ancient Egyptians lived in the days before sugar, so we can’t blame sugar for their dental disease. They ate a huge amount of grain and grain-based foods, a fari amount of fruits and vegetables, and very little meat. In fact they ate pretty much the kind of diet that today’s nutritionists would have us all eat to prevent disease. It didn’t do the Egyptians a whole lot of good. The calculus (tartar) deposits on their teeth were often so extensive that they held the teeth in place after death for 2,000 years. The result of these deposits is early bone loss, loose teeth, infection, and tooth loss. In addition, the ancient Egyptians had arteriosclerosis, obesity, rampant tooth decay, and a host of diseases that we consider ‘modern’ diseases.
Sticky, high-carb foods cause periodontal disease. The obesity, diabetes, and insulin resistance mentioned above are probably caused by high-carb diets. The papers mentioned above show that high-carb diets are associated with pancreatic cancer. So, despite the authors speculating about inflammation and increased gastric secretions, I think the periodontal disease data further confirms the hypothesis that excess carbohydrate consumption is more than likely the driving force behind pancreatic cancer.
As if you needed more, this is just another reason to follow a whole-food low-carbohydrate diet.