Yes, coconut oil does kill certain bacteria in your mouth, and recent research suggests it’s more selective than you might expect. Rather than wiping out everything indiscriminately, coconut oil appears to target harmful species while leaving beneficial bacteria intact. That said, the evidence is still limited enough that major dental organizations haven’t endorsed it as a substitute for brushing and flossing.
Which Bacteria It Targets
Your mouth contains hundreds of bacterial species, and not all of them cause problems. A healthy oral environment includes bacteria from groups like Streptococcus, Actinomyces, and Veillonella that help maintain balance. When gum disease develops, these beneficial species get displaced by harmful ones.
A 2025 triple-blind clinical trial published in Clinical Oral Investigations used advanced gene sequencing to track exactly which species changed after coconut oil treatment. The results were striking: coconut oil significantly reduced two bacteria central to gum disease, Tannerella forsythia and Treponema denticola, both members of the so-called “red complex” that drives the destructive process behind periodontitis. At the same time, beneficial bacteria actually increased. The researchers found that coconut oil “may reduce dysbiosis predominantly through the selective inhibition of pathogenic taxa without negatively impacting beneficial bacteria.”
Coconut oil also reduces Streptococcus mutans, the primary bacteria responsible for cavities. In a study of children who practiced oil pulling with coconut oil for two weeks, the average colony count of S. mutans in saliva dropped from roughly 5,700 to about 4,100 per milliliter. That reduction was statistically significant and comparable to results from a commercial children’s mouthwash.
How It Works
About 50% of the fat in coconut oil is lauric acid, a medium-chain fatty acid with well-documented antimicrobial properties. When lauric acid contacts bacterial cell membranes, it disrupts their structure. Bacteria have fatty outer layers, and lauric acid integrates into those layers and destabilizes them.
There’s also a mechanical component. When you swish coconut oil in your mouth for 15 to 20 minutes, the oil mixes with saliva and changes consistency, turning from clear to milky white and becoming thinner. One proposed explanation is that saliva’s natural bicarbonate breaks down the fat in a process similar to soap-making, creating an emulsion with greater cleaning power. The viscous oil also coats tooth surfaces and may physically prevent bacteria from adhering and forming plaque.
How It Compares to Mouthwash
A systematic review and meta-analysis compared oil pulling directly to chlorhexidine, the gold-standard prescription mouthwash used to treat gum disease. The findings were mixed. Chlorhexidine was still better at reducing plaque, with a meaningful advantage in plaque index scores. However, when researchers compared oil pulling to non-prescription mouthwashes, oil pulling actually performed significantly better at reducing gum inflammation.
The clinical trial using gene sequencing found that coconut oil improved the subgingival microbial dysbiosis index (a measure of how “out of balance” your mouth bacteria are) at a rate comparable to chlorhexidine. Both treatments shifted the bacterial community back toward a healthier composition. This is notable because chlorhexidine can cause tooth staining, altered taste, and increased tartar buildup with long-term use, while coconut oil has virtually none of those side effects.
How to Do Oil Pulling
The traditional method involves placing about one tablespoon (10 ml) of coconut oil in your mouth and swishing it gently between your teeth for 15 to 20 minutes. You don’t need to swish vigorously. Pull it through the gaps between your teeth with a gentle sucking motion, then spit it into a trash can (not the sink, where it can solidify and clog pipes). Rinse your mouth with water afterward.
Most people do this first thing in the morning on an empty stomach. The 15-to-20-minute duration matters because that’s how long it takes for the oil to fully emulsify with saliva and change consistency. Shorter sessions likely reduce the effect. If your jaw gets tired, you’re probably swishing too hard.
One Real Safety Concern
Oil pulling is generally safe, but there is one risk worth knowing about: accidentally inhaling the oil. Two documented cases of lipoid pneumonia, a rare lung condition, were linked to oil pulling. Both patients had repeatedly aspirated (breathed in) small amounts of oil during their sessions. Symptoms of lipoid pneumonia include persistent cough, fever, chest pain, and shortness of breath. Chronic cases can develop slowly with minimal symptoms, making them easy to miss.
To minimize this risk, keep the amount of oil manageable. If a full tablespoon feels like too much to control in your mouth, start with a teaspoon. Never tilt your head back while swishing, and stop if you feel any urge to cough or gag. Children and anyone with swallowing difficulties should avoid oil pulling entirely.
What Dental Professionals Say
The American Dental Association does not currently recommend oil pulling as a dental hygiene practice. Their position, stated on their consumer website MouthHealthy.org, is that “there are no reliable scientific studies to show that oil pulling reduces cavities, whitens teeth or improves oral health.” They continue to recommend brushing twice daily with fluoride toothpaste and flossing once a day.
This stance reflects the state of evidence as a whole: while individual studies show promising antibacterial effects, most have been small, and long-term outcomes like actual cavity prevention or reversal of gum disease haven’t been well established. The newer gene-sequencing research is encouraging, but it’s still just one trial. If you want to try oil pulling, treat it as a complement to your existing routine rather than a replacement for brushing, flossing, or professional cleanings.