The 4 Stages of Sleep & Their Importance

When you go to bed at night and wake up in the morning, you probably don’t give much thought to the time in between. Sometimes you have dreams and sometimes you don’t. A night of sleep is made up of multiple different stages. If you have sleep apnea or another sleep disorder, you may not be reaching all the stages of sleep, and this can be detrimental to your health. Continue reading to learn about the different stages of sleep and why they are important.

Stage One: Light Sleep

When you first drift off to sleep, your eye movements will start to slow down, and your body will remain alert to a certain degree. However, outside stimuli could still easily wake you for these few minutes. This stage only lasts between five to ten minutes. This stage can be considered as a transition period between wakefulness and sleep. If someone wakes during this time, they might not even realize they were asleep.

Stage Two: Fairly Light Sleep

During this time, you become less aware of your surroundings, your body temperature drops and your breathing and heart rate become more regular. Your brain produces bursts of rapid, rhythmic brainwave activity known as “sleep spindles.” The American Sleep Foundation reports that people spend approximately 50% of their sleep at this stage.

Stage 3: Deep Sleep

This stage causes your muscles to relax. Your blood pressure and breathing rate drop as well. This is when you are sleeping the deepest. You are less responsive to noise and activity around you. Deep, slow brain waves known as “delta waves” emerge at this time. This is your body’s chance to repair any muscles and tissues that were damaged during the day. This is also crucial for growth and development in children and teenagers.

Stage 4: REM Sleep

REM stands for “rapid eye movement.” During this stage, your brain becomes more active, your body becomes relaxed, and your eyes move rapidly. This is the time of night when you are most likely to have dreams due to the increased brain activity.

How Does Sleep Apnea Affect the Stages of Sleep?

If you have a sleep disorder, like obstructive sleep apnea, that keeps waking you in the night, you won’t be spending as much time in stages 3 and 4 of the sleep cycle. Most of the sleep you have will take place in stages one and two. Your physical and mental health will suffer as a result. For example, lacking sleep results in weaker immunity, higher blood pressure, memory issues, mood changes, and more. These issues will only get worse as time goes on.

If you are feeling fatigued during the day or are experiencing other signs of sleep apnea, it’s worth seeing a professional. This way, you can work toward quality, uninterrupted sleep.

About the Author

Dr. Kinnari Jariwala earned her dental doctorate from the University of Missouri-Kansas City School of Dentistry. Since then, she has been committed to continuing education, primarily focusing on sleep and TMJ medicine. She is a proud member of numerous professional organizations, including the American Board of Dental Sleep Medicine, the American Academy of Craniofacial Pain, and the American Board of Craniofacial Dental Sleep Medicine. For more information or to schedule an appointment at her office in Albuquerque, visit her website or call (505) 433-2107.