DW: Depends on where the kiss is...
This isn’t exactly great news. A study from Iran suggests that kissing might spread depression and anxiety between couples through mouth bacteria. Researchers followed 268 newlywed couples for six months, where one partner had depression, anxiety, and sleep issues, while the other was mentally healthy. They tested saliva for stress hormones and mouth bacteria. After six months, the healthy partners showed higher depression and anxiety scores, plus sleep problems. Their mouth bacteria also started to match their partner’s, with bacteria like Clostridia and Veillonella, linked to brain disorders, becoming more common.
Women showed bigger changes than men, with their stress hormone levels nearly doubling. The study says these bacteria might affect the brain by weakening the blood-brain barrier. While the findings show a link, they don’t prove kissing causes these issues, and more research is needed to confirm the connection. This suggests mental health could spread through close contact like kissing.
Source: NY Post