Sleep deficiency can cause you to feel very tired during the day. You may not feel refreshed and alert when you wake up. Sleep deficiency also can interfere with work, school, driving, and social functioning.
How sleepy you feel during the day can help you figure out whether you're having symptoms of problem sleepiness. You might be sleep deficient if you often feel like you could doze off while:
- Sitting and reading or watching TV
- Sitting still in a public place, such as a movie theater, meeting, or classroom
- Riding in a car for an hour without stopping
- Sitting and talking to someone
- Sitting quietly after lunch
- Sitting in traffic for a few minutes
Sleep deficiency can cause problems with learning, focusing, and reacting. You may have trouble making decisions, solving problems, remembering things, controlling your emotions and behavior, and coping with change. You may take longer to finish tasks, have a slower reaction time, and make more mistakes.
The signs and symptoms of sleep deficiency may differ between children and adults. Children who are sleep deficient might be overly active and have problems paying attention. They also might misbehave, and their school performance can suffer.
Sleep-deficient children may feel angry and impulsive, have mood swings, feel sad or depressed, or lack motivation.
You may not notice how sleep deficiency affects your daily routine. A common myth is that people can learn to get by on little sleep with no negative effects. However, research shows that getting enough quality sleep at the right times is vital for mental health, physical health, quality of life, and safety.
To find out whether you're sleep deficient, try keeping a sleep diary for a couple of weeks. Write down how much you sleep each night, how alert and rested you feel in the morning, and how sleepy you feel during the day.
Compare the amount of time you sleep each day with the average amount of sleep recommended for your age group, as shown in the chart in "How Much Sleep Is Enough?" If you often feel very sleepy, and efforts to increase your sleep don't help, talk with your doctor.
You can find a sample sleep diary in the National Heart, Lung, and Blood Institute's "Your Guide to Healthy Sleep."