A Houston dentist has sparked debate on TikTok by claiming that cavities can be transmitted through kissing. Dr Tasneem Mahmood's video, captioned 'And that's on cavities being contagious,' has amassed over a million views, warning that passionate embraces could spread tooth decay.
Experts have known since the 1970s that tooth decay is transmissible, according to Dr John Featherstone, professor emeritus at the University of California, San Francisco. The decay is linked to bacteria in saliva, which can be exchanged during kissing.
However, bacteria alone do not cause cavities. Frequent consumption of fermentable carbohydrates—such as sugars and bread—is essential for decay, as bacteria feed on them and produce acid that dissolves tooth enamel. Good dental hygiene, including brushing twice daily with fluoride toothpaste and limiting sugar intake between meals, can reduce risk.
Dr Featherstone notes that most people carry decay-producing bacteria but do not necessarily develop cavities. He advises against avoiding kissing altogether but recommends extra care if a partner has active decay, urging them to seek dental treatment.
