(NaturalHealth365)  For years, researchers have known that a common oral bacterium, Fusobacterium nucleatum, is found within colorectal tumors.  But new evidence published in Nature reveals a shocking discovery: only one distinct genetic strain of this oral microbe is driving colorectal cancer.

The study, led by an international team of scientists from Harvard, the Fred Hutchinson Cancer Center, and the University of Bologna, found that Fusobacterium nucleatum subspecies animalis (Fna) splits into two genetic clades – Fna C1 and Fna C2.  Only Fna C2 appears to colonize and thrive inside colorectal tumors.

The mouth-gut cancer link

Fusobacterium nucleatum normally lives harmlessly in the mouth.  But when oral health deteriorates – through gum bleeding, infection, or even aggressive brushing – the bacteria can enter the bloodstream and migrate to the colon.  Once there, this particular Fna C2 strain appears to create a favorable environment for tumor growth.

Researchers discovered that Fna C2 carries nearly 200 genetic adaptations that give it a survival advantage in the gut, enabling it to form protective biofilms and alter the surrounding metabolism.

Human studies found:

• Only Fna C2 was enriched in colorectal tumor samples, not in healthy adjacent tissue.

• Stool samples from over 1,200 participants showed the same dominance of Fna C2 among colorectal cancer patients.

According to lead author Dr. Christopher Johnston, “Our results identify a specific bacterial lineage that’s not just associated with colorectal cancer – it’s adapted to live and thrive within the tumor environment itself.”

Beyond cancer: The cardiovascular dangers

Oral bacteria don’t stop at the gut.  Bleeding gums – whether from periodontal disease, flossing, or mouth injuries – create an open gateway for F. nucleatum to enter the bloodstream.  Once circulating, it can trigger systemic inflammation and contribute to cardiovascular disease.

Researchers have shown that F. nucleatum’s metabolic byproducts can stimulate the production of clotting factors, such as prothrombin.  When these molecules meet inflamed or cholesterol-laden arteries, they can spark blood clots, raising the risk of heart attack or stroke.

This makes oral health more than a cosmetic concern – it’s a systemic one.

The flawed approach: Over-sanitizing the mouth

Many people reach for antibiotics or antiseptic mouthwash to “kill bad bacteria,” but this can backfire.  Harsh mouthwashes, especially those containing chlorhexidine or fluoride, disrupt the delicate oral microbiome.  This not only allows opportunistic fungi like Candida albicans to overgrow but can also reduce nitric oxide production, a key molecule for healthy blood pressure and circulation.

Oral bacteria help convert dietary nitrates (from vegetables) into nitrites, which the stomach turns into nitric oxide.  Destroying those bacteria with daily antiseptics can impair this pathway and elevate cardiovascular risk.

Natural protection: Restore balance, not sterility

Healthy oral ecology is about balance – supporting beneficial microbes while keeping pathogens like F. nucleatum in check.  Here’s how to naturally maintain that equilibrium:

• Brush twice daily and floss after meals.  This prevents biofilm buildup without disrupting the entire microbiome.

• Avoid daily antiseptic or fluoride-based mouthwashes.  Opt for natural alternatives made with green tea, saltwater, or essential oils.

• Eat polyphenol-rich foods.  Organic berries, leafy greens, and cruciferous vegetables help suppress tumor-promoting microbes.

• Support your immune system.  A healthy gut and liver enhance detoxification and prevent bacterial migration.

Modern oral hygiene should focus on microbial harmony, not chemical warfare.

Take control of your oral-systemic health

If you’re ready to understand the real connections between your mouth and your entire body, get access to Jonathan Landsman’s Holistic Oral Health Summit.

This exclusive program brings together 33 of the world’s top dentists, doctors, and natural healthcare experts, all revealing suppressed truths about gum disease, mercury fillings, root canals, and hidden infections that can trigger cancer, heart disease, and autoimmune illness.

This program is a must-watch for anyone seeking natural, science-based solutions to oral and systemic health.  You’ll discover how to detox from dental toxins, prevent disease at the root, and protect your heart, brain, and immunity for life.

Sources for this article include:

Nature.com