Medical cannabis may shift oral bacteria levels without changing saliva flow
In 16 patients starting medical cannabis, saliva volume and pH stayed stable over four weeks, but Lactobacillus levels increased significantly.
Quick Facts
What This Study Found
Lactobacillus growth scores rose significantly at both week 1 (p=0.033) and week 4 (p=0.025) compared to baseline. Streptococcus mutans showed a non-significant trend toward increase at week 4 (p=0.058). Saliva flow and pH remained unchanged.
Key Numbers
16 patients enrolled, 14 female, mean age 52.8 years. Lactobacillus scores: 2.59 (baseline), 3.1 (week 1, p=0.033), 3.3 (week 4, p=0.025). S. mutans scores: 1.8 (baseline), 1.6 (week 1), 2.4 (week 4, p=0.058).
How They Did This
Prospective study of 16 rheumatology patients newly approved for medical cannabis. Saliva samples were collected at baseline, week 1, and week 4, then measured for volume, pH, and microbial growth of S. mutans and Lactobacillus using a specialized culture kit.
Why This Research Matters
Cannabis is typically consumed orally (smoked, vaped, or ingested), meaning the oral cavity is the first biological system exposed. Changes in oral microbiome composition could have downstream effects on dental health.
The Bigger Picture
Higher Lactobacillus levels in the mouth are generally associated with increased cavity risk. If cannabis consistently shifts oral flora in this direction, it could have practical implications for dental care among regular users.
What This Study Doesn't Tell Us
Very small sample (16 patients). No control group. Short follow-up (4 weeks). Most participants were female fibromyalgia patients, limiting generalizability.
Questions This Raises
- ?Do these microbial shifts persist beyond four weeks?
- ?Does the route of cannabis consumption (smoking vs. oral ingestion) matter?
- ?Would these changes translate to measurable dental health outcomes?
Trust & Context
- Key Stat:
- Lactobacillus levels rose significantly within one week of starting cannabis
- Evidence Grade:
- Very small sample size with no control group and short follow-up period.
- Study Age:
- 2021 study from a single clinic in Israel.
- Original Title:
- The impact of medical cannabis consumption on the oral flora and saliva.
- Published In:
- PloS one, 16(2), e0247044 (2021)
- Authors:
- Habib, George(5), Steinberg, Doron, Jabbour, Adel
- Database ID:
- RTHC-03182
Evidence Hierarchy
Enrolls participants and follows them forward in time.
What do these levels mean? →Frequently Asked Questions
Did medical cannabis cause dry mouth in this study?
No. Saliva flow remained stable across all three measurement points (baseline, week 1, and week 4), with no significant changes.
What oral bacteria changed with cannabis use?
Lactobacillus levels increased significantly at both week 1 and week 4. Streptococcus mutans showed a trend toward increase at week 4 but did not reach statistical significance.
Read More on RethinkTHC
- CBD-oil-quality-guide
- anxiety-medication-after-quitting-weed
- cannabis-chemotherapy-nausea
- cannabis-chronic-pain-research
- cannabis-epilepsy-CBD-Epidiolex
- cbd-anxiety-research-evidence
- cbd-for-weed-withdrawal
- cbd-vs-thc-difference
- medical-benefits-of-cannabis
- quitting-weed-before-surgery
- quitting-weed-medication-interactions
- quitting-weed-pregnancy
- quitting-weed-pregnant
- seniors-older-adults-cannabis-risks-medications
- weed-breastfeeding-THC-breast-milk
Cite This Study
https://rethinkthc.com/research/RTHC-03182APA
Habib, George; Steinberg, Doron; Jabbour, Adel. (2021). The impact of medical cannabis consumption on the oral flora and saliva.. PloS one, 16(2), e0247044. https://doi.org/10.1371/journal.pone.0247044
MLA
Habib, George, et al. "The impact of medical cannabis consumption on the oral flora and saliva.." PloS one, 2021. https://doi.org/10.1371/journal.pone.0247044
RethinkTHC
RethinkTHC Research Database. "The impact of medical cannabis consumption on the oral flora..." RTHC-03182. Retrieved from https://rethinkthc.com/research/habib-2021-the-impact-of-medical
Access the Original Study
Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.
This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.