Ever wonder what your brain and body do while you sleep? Your body recovers and gets ready for the next day - easy enough... Turns out it is an incredibly active and dynamic process your brain and body undergo.

Many of you probably know that we sleep in stages. We've heard of REM and non-REM sleep. But what do these stages do? Why do we have different stages? What are they good for?

Understanding the stages of sleep is key to appreciating why quality sleep is essential for your health and wellbeing. Each stage plays a unique role in helping you recover physically, recharge mentally, and prepare for the challenges of the day ahead. Let’s dive in.

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Your sleep is organised into cycles that last approximately 90 minutes each. Throughout the night, you’ll go through 4-6 cycles. During a cycle your body sequences through four sleep stages. These stages are grouped into two categories: non-rapid eye movement (NREM) sleep and rapid eye movement (REM) sleep. Stages 1-3 are NREM and Stage 4 is the REM sleep stage. We briefly touched on this in Sleep & Productivity.

Stage 1: Light Sleep (NREM 1) 

The first stage of sleep is a brief transition from wakefulness to sleep. During the first stage your body begins to relax. Your heart rate slows, your breathing slows and your muscles release tension. This phase usually lasts just a few minutes and serves as the gateway to deeper sleep. You are still somewhat alert and easily woken. Ever had that sudden wake-up during a boring meeting just after lunch? You're suddenly awake and wonder if anyone noticed you were about to pass out on your chair? This is stage one.

NREM 1 is crucial for helping your body and mind transition out of wakefulness and prepare for the restorative stages ahead.

Stage 2: Deeper Light Sleep (NREM 2)

Stage 2 marks a deeper state of relaxation. Your body starts to settle into a more consistent rhythm. During this phase, your body temperature drops, breathing becomes steady, and your brain produces unique patterns called “sleep spindles”. These spindles are bursts of brain activity that help consolidate memories. This stage lasts around 20 minutes per cycle. NREM 2 plays a key role in supporting memory and learning.

Stage 3: Deep Sleep (NREM 3)

This is known as slow-wave sleep. Stage 3 is the most restorative phase of the sleep cycle. During this stage, your brain produces slow brain waves and you release growth hormones. The hormones help rebuild muscles and strengthen your immune system. Deep sleep tends to dominate the first half of the night and gradually decreases as the night progresses. This stage is essential for physical recovery, immune health, and overall vitality. 

Stage 4: REM Sleep

REM sleep is the final stage of the cycle. It is characterised by intense brain activity that closely resembles wakefulness. This is the phase where most dreaming occurs. Your body experiences rapid eye movements, irregular breathing, and temporary muscle paralysis. The muscle paralysis Is crucial so you don't act out your dreams.

The REM sleep stages grows longer as the night progresses, eventually making up about 25% of your total sleep. The stage is vital for emotional regulation, memory consolidation, and learning, as your brain processes and organises the experiences of the previous day.

So what?

We know that sleep is important (check out our blog post on Why We Sleep and Sleep and Productivity). Each stage contributes to your overall health, from physical restoration to emotional and mental rejuvenation. Important to note, ALL stages are critical. Trying to maximise deep sleep at the expense of REM sleep will not help you recover better...

Prioritising quality sleep and supporting your body with the right tools can unlock the full potential of these sleep stages. To ensure you cycle through all the stages of sleep effectively, focus on improving your sleep quality:

• Consistent sleep schedule - unfortunately unlikely to be a viable option amongst this group…
• Sleep-friendly environment - keep your bedroom dark, cool, and quiet. This is hopefully manageable for anyone reading this.
• Diet - Avoid caffeine and heavy meals before bed. You might have to get that cup of coffee to power through the late hours but do you really need that late night pizza snack in the office? Different story altogether if you're 17 double G&T's down.
• Exercise - if you can, do it in the mornings and not just before sleep. If your only work out option is in the evenings, then it's a judgment call to trade off sleep for exercise. Both are required for peak performance.

If you already do all the above but want to take it to the next level? Try Somio's SleepBites and optimise rest, one stage at a time.

We are not health professionals and the above represents our own personal view. Consider consulting with a health professional if you are unsure about a new supplementation regimen to ensure that it’s safe and appropriate for your individual needs.