Sleep Duration - The Apeiron Life Perspective

Elizabeth Bradley, MS
Feb 16, 2022
4 min read

Updated: Sep 1, 2022

What it is:

Getting sufficient sleep each night is essential for our health and wellbeing. Adequate sleep keeps us energized, sharp, and emotionally regulated. It allows the body and brain to detoxify and repair. As a result, sufficient, high-quality sleep lowers our risk for disease and helps us live longer.

Many of us have heard that eight hours of sleep each night is the optimal duration to strive for. However, there is no one-size-fits-all sleep duration that accounts for individual differences. Rather, current guidelines by sleep experts recommend an approximate range close to this instead.

The Purported claims:

Sleep, or a lack of it, affects total mind and body health in terms of:

Cognitive function, including reaction time, alertness, and decision-making
Emotional health, including how reactive, empathic, and threatened we are
Stress and anxiety levels
Our ability to learn and retain new information successfully
Social behavior and relationship-forming
Next-day appetite and food choices
Weight and obesity risk
Insulin sensitivity
Inflammation
Cancer risk
Total lifespan

What the science says:

Not all sleep is created equal, but having a consistent sleep schedule night after night can promote high-quality sleep rich in rapid eye movement (REM) and restorative non-REM sleep. Both types of sleep are essential for brain health. The American Academy of Sleep Medicine currently recommends that adults below 65 sleep for 7-9 hours per night. That’s approximately 50 hours, or more, of sleep per week. After age 65, this tends to decrease slightly to 7-8 hours.

Some people are more inclined to go to bed and wake up on the earlier end of the spectrum. These individuals are often referred to as “morning larks”. While others prefer to go to bed near or past midnight, sleeping in later in the morning (“night owls”). When we take alarm clocks and work schedules out of the equation, this natural preference is at least partially genetic and referred to as our “chronotype”. However, many studies generally link “morning types” with better health. This is potentially because our deepest sleep tends to happen during the first half of the night (before about 3 am). If we aren’t allowing ourselves enough time for this restorative, non-REM sleep, we run the risk of missing out on some of the rest and repair that our brains and bodies need.

The closer we get to morning, the more concentrated our REM sleep becomes. REM sleep is associated with memory formation and emotion processing. While it’s important that we don’t miss out on deep sleep, getting up too early in the morning (for example, to exercise or begin the workday) can deprive us of some of the benefits of REM. Therefore, it’s important to find a happy medium that isn’t too early or late, or most importantly: too short.

There is a caveat, however. It’s a common misconception that more sleep is better. The relationship between sleep duration and health is U-shaped. This means that both short sleep (less than 6 hours per night) and long sleep (greater than 9 hours per night) are both associated with worse health. Therefore, if you feel energized and well-rested on 7 hours of sleep, rather than, say, 8 or 9, don’t panic; this is probably the right amount for you.

Our take:

Each of us differs in terms of how much sleep is the right amount, but most adults should strive for somewhere within the recommended guidelines of 7-9 hours. Sufficient sleep leaves us feeling replenished, energized, and able to tackle the day. Whether you’re able to do so after 7 hours or 9 hours, or something in between, is specific to you and must not be compared to anyone else.

These days, it can be tricky to resist the urge to sacrifice sleep for extra hours at the desk, or gym, but the evidence is abundantly clear that putting sleep first helps us in all areas of life. It allows us to focus better when we are at work, have the emotional bandwidth to support family and friends, prevent injury and illness, and recover from these things more quickly.

You know you are sufficiently rested when getting out of bed leaves you feeling refreshed. Spend too much time in bed and it can often lead to grogginess. The important thing is working out what is right for you and sticking to it as consistently as you can.

Will this benefit you?

Yes, getting consistent sleep of sufficient duration is one of the best steps you can take to be in better health and increase your lifespan. It is one of the best preventatives against cognitive decline, cancer, and cardiovascular disease.

The body is resilient and can cope with the occasional late night, but do your best to stick to regular sleep times and strive for at least 50 hours per week.

Still curious to try it? If you do, here’s what to keep an eye on:

It’s important to be aware that absolute sleep duration is not equal to the total time we spend in bed. It takes time to unwind and drift off to sleep after getting into bed and we often wake up once or twice during the night. For this reason, you must allow adequate sleep opportunity to get the full 7 hours or more each night.

The amount of sleep we get is a balance of two polarizing forces:

How much time we allow ourselves in bed
How much external factors prevent our sleep (e.g. stress, a loud bed partner, or caring for a sick child)

To get at least 7 hours of sleep per night. Allow yourself closer to 8 hours of sleep opportunity (scaling this up appropriately if you need closer to 8 or 9 hours of sleep).