- 73% of French people say they wake up at night, according to a 2025 survey for the National Institute of Sleep and Vigilance.
- In some people, these nighttime awakenings are caused by higher levels of the stress hormone cortisol.
- Certain actions can help anticipate and counter this cortisol peak.
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Sleep: dive into the arms of Morpheus
Nocturnal awakenings are a sleep disorder (new window)the most frequent. According to an OpinionWay survey for the National Institute of Sleep and Vigilance (INSV (new window)) on the occasion of Sleep Day 2025, 73% of French people say they wake up at night, twice a night. Ultimately, this sleep disorder can cause fatigue, mood disorders, concentration problems, but also memory problems. As relayed by Health Insurance (new window)more than half of insomnia (new window) and difficulty sleeping well are due to stress, anxiety and depression.
In a study published in 2015 in the scientific journal Sleep Medicine
(new window)and relayed by mentalist Fabien Olicard, these nocturnal awakenings are caused by a peak in cortisol. As the Brain Institute reminds us (new window)it is a steroid hormone produced by the adrenal glands which plays a role in the regulation of stress, metabolism and even the immune system. Its secretion follows a circadian rhythm, its production is generally higher in the morning in order to promote wakefulness and activity. The peak which occurs between two and four in the morning thus serves to prepare us for waking up. However, in people suffering from stress, this peak can turn into a “hormonal tsunami”, as the brain enthusiast relays in a video (new window) published on his social networks. The study published in Sleep Medicine
which followed 1,200 people for six months established that people who regularly woke up in the middle of the night had a 40% higher level of cortisol in their blood than others. The Brain Institute explains that “the circadian cycle can, however, be disrupted by stressful events or lifestyle habits (night work, irregular sleep)”
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What is the 3-2-1 method to reduce stress before sleeping?
To prevent the cortisol peak from disrupting sleep, researchers established the 3-2-1 protocol which represents several actions to implement to relax before bedtime. Three hours before going to bed, it is therefore advisable to stop eating. If you go to bed at 10:30 p.m., dinner should be around 7:30 p.m. Two hours before bedtime, you should stop working or dealing with stressful subjects. Instead, it is advisable to do activities that relax you. Finally, one hour before sleeping, you must stop all forms of screen use, from smartphones to television. Instead, it is recommended to read or devote a few minutes to meditation to help you fall asleep. Fifteen days after application of the protocol, nighttime awakenings decreased by 60% among the people concerned according to the researchers of the study published in 2015.
