Bleeding Gums While Brushing May Signal Colorectal Cancer Risk, Study Finds

Oral changes such as bleeding during brushing or persistent bad breath may be linked to colorectal cancer risk beyond simple dental problems, according to recent research. The findings suggest that gut health and oral bacterial environments can influence each other.

According to the British Daily Mail on the 15th (local time), recent studies have shown that an imbalance in oral bacteria leading to an increase in certain bacteria may be associated with colorectal cancer risk.

Dr. Mark Burhenne, a dental specialist known online as "the sleep dentist," explained that common oral symptoms such as bleeding gums or persistent bad breath could signal changes in the bacterial environment.

While beneficial bacteria exist in the mouth to help maintain health, harmful bacteria can become dominant, causing inflammation. Some bacteria may then travel to the digestive system through saliva or blood. Researchers suggest this process could trigger intestinal inflammatory responses and potentially create an environment conducive to cancer cell growth.

Bleeding gums during brushing is considered a hallmark sign of gum disease. According to research from Harvard University, people with gum disease have a 17-21% higher risk of developing polyps in the colon, known as precancerous growths. Swollen gums or pain when touched may also indicate early inflammation, and such conditions are often left untreated for extended periods.

Persistent bad breath may also be linked to specific bacteria. A bacterium called Fusobacterium nucleatum, known to cause gum disease, has been found in high concentrations in colorectal cancer tumor tissues. Researchers believe this bacterium may travel to the intestines through saliva or blood and help cancer cells evade immune responses.

Tongue coating, a white or yellow film on the tongue, is also cited as a sign of changes in the oral bacterial environment. Tongue coating forms from accumulated bacteria, food debris, and dead cells, with poor oral hygiene, dehydration, and dry mouth identified as main causes. Some studies suggest tongue coating may reflect changes in oral microbiome and warrant further research on its connection to gut health.

Research has also linked tooth loss from gum disease to gut health. According to data from Harvard University and the American Association for Cancer Research (AACR), people who have lost four or more teeth due to long-term gum disease have approximately 20% higher risk of developing precancerous polyps in the colon.

However, experts emphasize that oral symptoms alone cannot confirm colorectal cancer. Instead, they advise maintaining oral hygiene through proper brushing, flossing, and regular dental checkups.

For colorectal cancer prevention, experts stress the importance of regular screenings along with lifestyle management including a balanced diet, regular exercise, smoking cessation, and moderate alcohol consumption.