A recent discussion about whether cavities can be “contagious” has gone viral on social media, after a medically-informed user shared an interesting classroom fact. The post quickly drew attention and sparked anxiety among thousands of netizens. Doctors have now weighed in, clarifying that while certain oral bacteria can be transmitted through saliva, the risks should be understood in context.
Can Cavities Be Transmitted? Social Media Sparks Panic
On Threads, a user joined a “Didn’t Know This?” challenge, writing: “Cavities can be contagious! Learned this in med school and was shocked 🤯.” The post quickly gained over 15,000 likes and responses, with many commenting in alarm: “Does this mean kissing someone with cavities is dangerous?” and “No wonder my whole family has bad teeth.” Some users even joked about avoiding blowing on their kids’ food after learning this.
The Science Behind “Kissing Disease”
Pulmonologist Dr. Huang Xuan explained that a phenomenon called “kissing disease” does exist medically. Studies show that a 10-second deep kiss can exchange roughly 80 million bacteria, and long-term partners can share up to 34% similarity in oral microbiota. Most bacteria have minimal effect on healthy individuals, but certain pathogens—including Streptococcus mutans (linked to cavities), EB virus (mononucleosis), HSV-1 (cold sores), and H. pylori—can be transmitted through saliva.
Could Cavities Become a “Couple’s Disease”?
Dr. Huang noted research showing that after a 10-second kiss, the similarity of cavity-causing bacteria in partners’ saliva can increase by about 20%. This suggests that poor oral health in one partner could slightly increase exposure risk for the other. EB virus can cause fever, sore throat, and swollen lymph nodes, while active cold sores carry a higher risk of viral transmission.
Tips to Reduce Transmission Risk
To minimize risk, Dr. Huang recommends maintaining good oral hygiene: brushing at least twice daily, flossing, and using fluoride or chlorhexidine mouthwash when necessary. He also suggested practical “kiss-safe” guidelines: regular dental check-ups, H. pylori screening if needed, limiting deep kisses for immunocompromised individuals, opting for cheek kisses instead, and avoiding touching eyes immediately after kissing.
By following these practices, couples can enjoy intimacy while reducing the risk of transmitting oral bacteria and infections.
