What Happens While We Sleep?

The Science of Sleep

There is nothing as satisfying as a good night’s rest, that feeling of waking up feeling restored, rejuvenated and ready to tackle the day. Sleep is an essential function within our bodies just like digestion and circulation, regulated by hormones and orchestrated by the brain.

Sleep is as important to our survival as food and water; we need it so we can repair and recharge all our systems. This daily (or nightly) recovery ensures our ability to properly function both cognitively and physically both the next day and the coming days.

We all know we NEED sleep, but what’s actually going on when we close our eyes and succumb to dreamland?

Let’s find out.

What happens when we sleep?

Scientists used to believe people were mentally and physically “inactive” while they slept, almost catatonic. While it may appear a person is completely incapacitated during sleep, there is an abundance of activity happening within our brains and bodies behind those closed lids.

Your brain is the conductor of your nightly sleep. Multiple parts of your brain are communicating throughout the night, creating hormones and other chemicals to move you through the cycles of non-REM and REM sleep.

As part of this nightly ritual, thousands of neurons in your brain switch from a waking to a sleeping state. This change sends signals throughout your body that it’s time to get to work.

  • Muscles, cells, organs and systems repair themselves from the day’s activities
  • Chemicals needed to strengthen the immune system begin to circulate
  • Our brain clears out unneeded information and toxins that build up
  • Pathways in your brain that let you create memories and learn new things are recharged
  • Your breathing, heart rate, pulse, blood pressure and overall energy expenditure slows down (during non-REM sleep)

Why do we need to sleep for optimal health?

While scientists are still uncertain about the biological purpose of sleep, what we do know is that without it, our cognitive and physical capabilities suffer.

Without consistent restorative sleep, our body is unable to repair and strengthen itself. Here’s what happens:

  • CARDIOVASCULAR: Your heart becomes more prone to stroke, coronary heart disease, diabetes and heart disease because lack of sleep can contribute to problems with blood pressure.
  • IMMUNE SYSTEM: You may get sick more easily; a tired immune system cannot appropriately fight off illness.
  • COGNITION: Lack of sleep impacts your problem-solving skills, makes it more difficult to think or reason clearly and affects your decision making. You may be forgetful and have trouble concentrating. In addition, you will be less alert and have slower reaction times when you are low on sleep.
  • CANCER RISKS: The risk of certain cancers is associated with not getting enough sleep, particularly prostate, breast and colorectal cancers.
  • METABOLISM: Multiple hormones are regulated during sleep, including melatonin, cortisol, leptin and growth hormones. Your body’s metabolism can be affected if hormone production is compromised, making you more prone to gaining weight and developing adult onset diabetes.

How to achieve restorative sleep.

Sleep hygiene is a ritual that will allow your brain and body a better chance of catching those ZZZZZs.  A regular bedtime AND wake time are important for creating the habit of getting the proper amount of sleep each night.

Here’s a few ways to create a bedtime routine that will prepare you for sleeping:

  • Turn down the thermostat, lower temperatures are better for sleeping.
  • Choose a consistent time to turn off your phone and other electronic devices. The light from these items keep the brain in an active state.
  • Dim the lights at a certain time of night.
  • Find an activity that allows you to quiet your body and your mind. It could be nightly stretches, journaling, a cup of warm tea or a relaxing shower.
  • Avoid caffeine, sugar and energy drinks as much as possible (or at least do not consume them in the hours before bed).
  • Stop drinking alcohol at least two hours before bed and avoid nicotine completely.
  • Exercise at least 20-30 minutes each day, although not in the hours leading up to bed.

How much sleep do you need?

In general, 7-9 hours of sleep is best for adults, and we all know that babies, children and teens need more. You may know someone who is able to function well on only a few hours of sleep each night, but this is not a healthy or sustainable habit.

It’s been suggested that some people can develop a tolerance to chronic sleep deprivation. What’s happened is they have become accustomed to less sleep, and this feels normal for them. However, their brains and bodies are indeed struggling due to lack of proper restorative sleep. This ongoing deprivation of sleep can lead to some of the adverse effects we discussed earlier.

There are over 80 recognized sleep disorders, and nearly 70 million Americans suffer from them. If you are having trouble with your sleep, it is important to talk to your doctor. Determining the root cause of your inability to gain the restorative sleep you need is critical to your long-term health and wellness.