Sleep expert Dr. Chris Winter says keeping a room cool at night significantly affects our ability to fall asleep.
It is recommended to maintain a temperature level between 15-20 degrees Celsius in the room where we sleep. A warm bedroom causes the body to stay awake and may impair the body's REM sleep, which is a stage in which the brain enters into dream sleep. Another method he says helps many of his patients is to keep the pillowcase in the freezer until bedtime. Another study found that sleeping in a cool room relieves stress and anxiety.