Plain and simple, the purpose of this guide is to explain the science of how to sleep better. You can click the links below to jump to a particular section or simply scroll down to read everything. At the end of this page, you’ll find a complete list of all the articles I have written on sleep.
I. The Science of Sleep
- The Purpose of Sleep
- How Much Sleep Do You Need?
- The Cost of Sleep Deprivation
- The Theory of Cumulative Stress
- Ok, But Can You Catch Up on Sleep?
II. How Sleep Works
- The Sleep-Wake Cycle
- Age-Related Sleep Changes
- The Circadian Rhythm
- The 2-Process Model of Sleep Regulation
III. How to Sleep Better
- How to Fall Asleep Fast
- How to Improve Sleep Quality and Duration
- Daily Habits for Better Sleep
- Natural Sleep Aids
I. The Science of Sleep
Sleep is one of the strangest things we do each day. The average adult will spend 36 percent of his or her life asleep. For one-third of our time on earth, we transition from the vibrant, thoughtful, active organisms we are during the day and power down into a quiet state of hibernation.
But what is sleep, exactly? Why is it so important and so restorative for our bodies and minds? How does it impact our lives when we are awake?
The Purpose of Sleep
Sleep serves multiple purposes that are essential to your brain and body. Let’s break down some of the most important ones.
The first purpose of sleep is restoration. Every day, your brain accumulates metabolic waste as it goes about its normal neural activities. While this is completely normal, too much accumulation of these waste products has been linked to neurological disorders such as Alzheimer’s disease.
Alright, so how do we get rid of metabolic waste? Recent research has suggested that sleep plays a crucial role in cleaning out the brain each night. While these toxins can be flushed out during waking hours, researchers have found that clearance during sleep is as much as two-fold faster than during waking hours.
The way this process occurs is fairly remarkable:
During sleep, brain cells actually shrink by 60 percent, allowing the brain’s waste-removal system—called the lymphatic system—to essentially “take out the trash” more easily. The result? Your brain is restored during sleep, and you wake up refreshed and with a clear mind.
The second purpose of sleep in memory consolidation. Sleep is crucial for memory consolidation, which is the process that maintains and strengthens your long-term memories. Insufficient or fragmented sleep can hamper your ability to form both concrete memories (facts and figures) and emotional memories.
Finally, sleep is paramount for metabolic health. Studies have shown that when you sleep 5.5 hours per night instead of 8.5 hours per night, a lower proportion of the energy you burn comes from fat, while more comes from carbohydrate and protein. This can predispose you to fat gain and muscle loss. Additionally, insufficient sleep or abnormal sleep cycles can lead to insulin insensitivity and metabolic syndrome, increasing your risk of diabetes and heart disease.
All of this to say, that better sleep is critical for your mental and physical health. Before we get too deep into this sleep guide though, let’s pause for just a second.