The nighttime behaviours doctors take very seriously
You wake up exhausted without knowing why, even though you slept for several hours? Certain nighttime behaviours silently disrupt sleep, without the person affected ever connecting them to their next-day fatigue. According to data from the French national health insurance body, 45% of French people are affected by at least one sleep disorder.
When fatigue has no obvious explanation
Doctor Janice Johnston highlights this in an article published on 2 August 2026 on the HuffPost US website: most people only become aware of a sleep problem when they experience excessive fatigue upon waking. Yet drawing a direct link between that fatigue and symptoms such as nasal congestion, digestive issues or pain often remains difficult.
That is precisely where the danger lies. Some of these nighttime behaviours signal disorders that require medical attention, even when nothing seems alarming at first glance. Several doctors have identified concrete warning signs to watch for.
Nighttime behaviours linked to sleep apnoea
Sleep apnoea is characterised by repeated pauses and resumptions in breathing during the night. The condition can manifest in several ways, and some signs are easily overlooked.
- Breathlessness during sleep: while sleeping, muscles relax and the throat can narrow or close, according to Dr Zeeshan Khan.
- Post-nasal drip: excess mucus running down the back of the throat can obstruct the airways and trigger temporary breathing stoppages.
- Snoring: this results from a narrowing of the airways, at the level of the nose or throat, which causes the surrounding tissue to vibrate.
- Dry mouth upon waking and nasal congestion can accompany these breathing episodes.
Dr Zeeshan Khan notes that snoring can also be accompanied by sniffling during the night or difficulty breathing. Taken together, these signs form a clinical picture that warrants a consultation.
Parasomnias: nighttime behaviours not to ignore
Parasomnias encompass unwanted behaviours or experiences that occur during sleep. They are often poorly understood, as the person affected does not always remember them.
Sleepwalking is one example. According to Zeeshan Khan, this disorder occurs during the deepest stage of non-REM sleep, when the brain is in an intermediate state between sleep and wakefulness. Sleep deprivation, stress or anxiety can all trigger it.
Talking in one’s sleep, known as somniloquy, is one of the most common parasomnias. Its cause remains unknown to this day. It is more prevalent among people with mental health conditions and can be associated with sleepwalking as well as nightmares, again according to Zeeshan Khan.
Chronic nightmares: an underestimated risk
Among the most concerning nighttime behaviours, chronic nightmares deserve particular attention. Anxiety and depression are among the most common psychological factors that trigger them.
These nocturnal episodes are not trivial. Janice Johnston warns that chronic nightmares can have serious health consequences, including an increased risk of suicide, heart disease and obesity. Treatment may therefore become necessary once they cause significant distress.
These nighttime behaviours illustrate just how much sleep functions as an indicator of overall health. Snoring, talking in your sleep or getting up in the night are not mere quirks: they are signals that doctors take seriously. Identifying these signs is the first step toward addressing them, because some of these nighttime behaviours call for professional care that patients cannot navigate alone.
