CBD Reduces Bacteria That Causes Gum Disease, Finds New Lab Study

A new laboratory study finds that cannabidiol (CBD) may reduce levels of bacteria linked to periodontal disease, including some of the most well-known pathogens involved in gum inflammation and tissue damage. Published by the Journal of Oral Microbiology, the research was conducted by scientists from Guarulhos University, Universidad Antonio Nariño and Pontificia Universidad Javeriana. The team examined how CBD affected a complex, multi-species subgingival biofilm designed to mimic the bacterial communities that form beneath the gum line in periodontal disease.

Researchers cultivated biofilms containing 33 different bacterial species using a standardized laboratory model. CBD was tested under two different treatment protocols and at several concentrations, with chlorhexidine, a common antimicrobial mouthwash ingredient, used as a comparison.

Under the first protocol, where biofilms were continuously exposed to CBD, concentrations of 250 and 500 µg/mL significantly reduced total bacterial counts. At the higher concentration, CBD also lowered the proportion of the so-called red complex, a group of bacteria strongly associated with advanced periodontal disease, and reduced levels of 10 individual species. Chlorhexidine produced broader effects, reducing 20 species.

In the second protocol, which more closely resembled intermittent oral care use, CBD at 1000 µg/mL again reduced total bacterial counts and decreased the red complex while increasing bacteria associated with the green complex, which is generally considered less pathogenic. Notably, both experimental approaches led to reductions in Porphyromonas gingivalis and Tannerella forsythia, two key periodontal pathogens.

The authors conclude that CBD demonstrated measurable antimicrobial activity in this laboratory model, particularly against bacteria linked to gum disease. They caution, however, that the findings are exploratory and emphasize the need for well-designed human studies using standardized bacterial measurements before any clinical conclusions can be drawn.