
09/25/2025
A fascinating new study suggests that toothbrushing does more than just freshen breath and protect against cavities. Researchers found that saliva collected shortly after brushing had a significantly stronger ability to neutralize the influenza virus in lab tests. In simple terms: keeping the mouth clean may actually strengthen saliva’s natural defense system, at least for a short time.
Saliva isn’t just water. It’s loaded with protective proteins, enzymes, and antibodies that form the first line of defense against germs entering through the mouth and nose. The study showed that after a thorough 5-minute brushing session, these natural antiviral properties were boosted — likely because brushing reduces harmful bacteria that can interfere with saliva’s protective functions.
The effect, however, was temporary. Antiviral activity was highest just 5 minutes after brushing and gradually reduced after an hour. That means oral hygiene alone cannot prevent flu infection — vaccines, hand hygiene, and masks remain essential. But this research highlights an important point: maintaining good oral health doesn’t just protect teeth and gums, it may also support the body’s wider immune defenses.
📄Research paper:
Kubo, Y., Iwamoto, T., Tobe, S. et al. Enhanced anti-influenza virus activity of saliva following toothbrushing. BDJ Open 11, 68 ( Published 19 july, 2025).