At night, however, this dynamic changes. The muscles of the mouth and face relax deeply during sleep, and this relaxation makes it easier for saliva to escape without us having any control over it. Furthermore, our sleeping position has a major impact. Sleeping on your stomach, for example, causes gravity to favor saliva flow, while sleeping on your side can also favor it depending on the tilt of your head.
The brain doesn’t stop while we sleep; in fact, it’s very active, alternating between different sleep phases: REM and non-REM.
During REM sleep, which is the phase in which most vivid dreams occur, the body’s muscles relax even more, and although saliva production may decrease, the risk of saliva leakage increases due to the extreme relaxation of the mouth muscles. This combination makes drooling during this phase quite common and often unavoidable. The brain, although aware of internal saliva signals, cannot intervene during deep sleep, so saliva leakage occurs silently.
There are physical and health factors that can cause some people to drool more than others. Nasal congestion is a classic example: when we have difficulty breathing through the nose, the body tends to breathe through the mouth, and this causes saliva to leak more easily. Similarly, certain medications and medical conditions that affect saliva production, swallowing, or muscle coordination can also increase the likelihood of drooling.Buy vitamins and supplements
Even habits such as smoking or consuming alcohol before bed can disrupt natural saliva production or affect how facial muscles handle swallowing during the night.
