The older you get, the fewer hours of sleep you need. Most people do not know when they are sleepy. Raising the volume of your radio will help you stay awake while driving. Sleep disorders are mainly due to worry or psychological problems. The human body never adjusts to night shift work.
Most sleep disorders go away even without treatment.
But only 5 percent had consulted a physician or sleep specialist about it. More than a third said they were so sleepy during the day that it interfered with their daily activities. Twenty-three percent admitted to falling asleep at the wheel in the past year. A hard-working man I know once read that the brain needs only four hours of sleep a night, so he trained himself to sleep no more than that. But while you can teach yourself to sleep less, you cannot teach yourself to need less sleep.