You may have heard it’s important to get good quality sleep, but do you know how much sleep you actually need for good overall health? For brain health, optimal performance, energy levels, sugar cravings, recovery, digestion, decision-making, mood stability, hormone health, and more, the importance of prioritizing sleep can not be understated.

Non-REM Sleep Versus REM Sleep

In order to dive deeper into sleep, we need to examine the different stages of a sleep cycle. Our sleep cycle can be broken up into two basic phases: Non-REM (rapid eye movement) sleep and REM sleep.

Non-REM

Non-REM sleep can be broken down into three stages.

Stage 1 is the in-between phase where you’re not fully awake, but you’re not entirely sleeping. Your heart rate typically slows, and your muscles relax.

Stage 2 involves being in a light sleep where brain waves begin to slow down and body temperature drops.

Stage 3 is where the most restorative sleep happens. Heart rate and breathing slow to their lowest levels, your body increases blood supply to your muscles for repair, hormones are released, and energy levels become restored.

REM

After about 90 minutes of being asleep, we enter REM sleep. In REM, the brain and body are energized, breathing becomes faster, eyes dart back and forth, and limbs become immobile. In this stage, the regions in the brain associated with memory, learning, and mood stability are stimulated.

REM sleep is commonly characterized by being the stage where we dream, but dreaming can also occur outside of REM. Even though certain brain regions are stimulated during this stage, researchers are still unsure why we dream. Some experts believe that dreaming helps consolidate and analyze memories and is a product of our imagination. Sleep studies have shown that brainwaves are just as active during REM as they are when we’re awake!

Does Sleep Differ Between Men and Women?

Although many researchers agree that adults should get 7-9 hours of sleep per night, there is some emerging scientific evidence that men's and women's sleep cycles differ.

Because women have fluctuating hormones that coincide with phases of the menstrual cycle, it may create an increase in sleep disturbances. Going even deeper into women’s hormones and sleep, throughout a woman’s lifespan and during specific time points (generally speaking), such as puberty, pregnancy, and menopause, sleep quality can be greatly impacted. This makes balanced hormones vital for good sleep health. One of the ways you can support your hormones, and therefore sleep, is by focusing on your circadian rhythm, or sleep-wake schedule. Having a consistent sleep-wake cycle means going to bed and rising at relatively the same time–even on the weekends.

CIRCADIAN RHYTHM

Research shows that a consistent sleep-wake schedule is even more important for your circadian rhythm than how much time you sleep. Going to bed at the same time and setting a consistent wake-up time allows your body to create a conscious rhythm to follow and adapt to. This rhythm triggers your body to naturally wind down to prepare for rest. In turn, your sleep latency (the amount of time it takes you to fall asleep) gets shorter. Less time falling asleep = more restful sleep!

Researchers from the UK studying circadian rhythms found that melatonin, the “calming” hormone that is released in the evening and triggered by darkness, is secreted earlier in women in comparison to men. Because of this, women tend to go to bed earlier and wake up earlier than men. Changes in hormones impacting circadian rhythm and vice versa, women often report needing more sleep to compensate.

Being in sleep debt and having poor sleep quality long-term is linked to having higher risks of hypertension, mood disorders like anxiety and depression, a weakened immune system, increased sugar cravings, insulin sensitivity, and makes you more susceptible to chronic diseases such as certain cancers, heart disease, and obesity.

Sleep Hygiene

It goes without saying that sleep is important for us all. Creating a consistent sleep-wake cycle and prioritizing sleep hygiene will provide mental and physical benefits. In a previous blog post on sleep, I covered ways I optimize sleep hygiene.

Here are my go-to practices: