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  • Carol Kennedy

The Power of Sleep

Recently I was listening to a podcast by Dr Rangan Chatterjee about sleep. One of his quotes that really stuck with me was “The shorter your sleep, the shorter your life” and when you read the reasons below it's obvious why this would be the case.

None of us live a perfect life or have the perfect routine that we can stick to 100% of the time but if we look at sleep as an investment in your lifespan and your health and treat it as a priority it actually helps us with every other aspect of what’s going on in our lives at the time whether that's in our metal, emotional metabolic, cardiovascular health etc.

Types of sleep

As adults we have an approximate sleep cycle length of 90 minutes. In the early part of the night they tend to be ‘Deep non REM (rapid eye movement) sleep’ and later in the night towards the early morning we move into ‘REM sleep’ which is our dream state.

REM sleep has been proven to increase lifespan and promote productivity.

Dr Chatterjee described it as “emotional first aid” in his podcast as it acts as a type of overnight mental health therapy. While we’re in our dream state the body processes difficult or traumatic experiences from our day to takes the sharp edges off these emotional concerns resulting in a type of self soothing that we’re completely unaware of.

We wake the next morning having processed the emotions and feel better about whatever it was that was bothering us. The saying is usually that time heals, but it’s actually time during sleep, specifically REM sleep, that heals!

The effects of a lack of sleep

We’ve all heard it, you should sleep for 7-9 hours a night ideally. Well back in the 1940’s, that’s exactly what we were doing but nowadays, the average adult sleeps for just 6.5 hours each night. The effects this difference can have on our human body are substantial.

  • If you are under-slept and on a weight loss journey you’ll find it harder to lose the weight you’re aiming for. 70% of weight loss in this state is from lean muscle mass instead of fat

  • Research has shown that people who sleep 5-6 hours per night are more likely to eat an additional 200-300 calories the following day. This is mainly to do with a change which occurs in your hunger hormones. Leptin (I’m full and don’t want to eat more) levels drop and Ghrelin (I’m not satisfied, give me more food!) increases.

  • After a shorter night’s sleep you wake up the next day with a lower level of motivation to exercise. If you do train, the intensity of your workout is generally lower so your activity is less effective and less efficient. This affects both the muscles and your respiratory system too with oxygen/carbon dioxide levels being altered too.

  • Sleeping less can also compromise your immune system. It’s been shown that someone who sleeps just 5 hours per night is 4 times more likely to catch a cold than someone sleeping 8 hours! It doesn’t take a week of bad sleep for this to happen, 1 night is enough to affect the immune system. Someone sleeping just 4 hours in 1 night has a 70% drop in natural killer cells the following day! These killer cells are part of our innate immune response and help decrease cancer risk and fight infections.

  • After a night of 5-6 hours sleep your focus and productivity levels plummet and are the same as having a blood alcohol limit of 5%

What happens to the body when we do get enough sleep?

Sleep, diet & physical activity are all interlinked. If you improve your sleep, your diet and physical activity levels will improve. Improve your diet and/or physical activity levels and you’ll automatically enhance your quality and quantity of your deep sleep.

When we sleep well our autonomic nervous system changes and the parasympathetic branch kicks in resulting in more deep sleep, a calmer mind, a decreased heart rate, reduced blood pressure, cortisol (stress hormone) levels drop and our body goes into immune stimulation mode so we can wake the next day and fight infection.

Have you ever wondered why we just want to sleep when we’re sick? An infection in our body indicates to the immune system that we’re under attack, this then sends signals to the sleep system in the brain that we need more deep sleep. Sleep is the best way to combat this infection. Our body’s want to sleep us, well!!

The main benefits of a good night's sleep include;

  • Reduces risk of disease including type 2 diabetes & heart disease

  • Increased energy

  • Improved mood

  • More motivation

  • Improved food choices

  • Improved physical performance

  • Stronger immune system

  • Better levels of focus & productivity

Tips for getting more sleep

  • Avoid alcohol - this caused a disturbed sleep so you’ll wake feeling fuzzy headed and unmotivated

  • Minimise caffeine after noon - believe it or not, 25% of the caffeine from that midday coffee will still be in your body at midnight! Aim to consume any caffeine you do have in the morning to allow your body to fall into a deep sleep through the night

  • Dim the lights - our bodies need darkness to increase our sleep hormone (melatonin) levels which helps time a healthy onset of sleep

  • No screen time 1 hour before bed, including phones, laptops & tv - blue light emitted from devices can impact our melatonin levels causing disturbed sleep and also cause eye strain resulting in headaches the next morning. Have a look at some blue light blocking glasses to wear in the evening which can help minimise the effects

  • Have a regular bedtime - this will create a new habit which your body’s internal clock will adjust to. You’ll benefit by sleeping more deeply and finding it easier to wake in the morning

  • Room temperature - the ideal bedroom temperature is 18-18.5 degrees Celsius to promote the most optimal sleep conditions

  • Get ready for bed 1 hour before - this will save you time when it comes to bedtime. Get changed, brush your teeth etc. It’ll also stop any late snacking which can affect digestion and keep you awake for longer

  • Create a wind down routine and stick to it, even on the weekends ;) - this could include having a relaxing bath, reading a few chapters of a good book, meditating, doing some light stretching, adding some calming essential oils to your diffuser, for example. Find what works for you.

  • How can you even get a little bit more sleep? Set a ‘Go to bed’ alarm, allow yourself to snooze it if need be. Having it go off will remind you to go to bed soon even if you do snooze it a couple of times first. Even an additional 15 minutes extra sleep per night can have a difference to your health & wellbeing. Go to bed 10 minutes earlier and set your wake up alarm for 5 minutes later.

Try a few of these things out for a week and see if your sleep improves. When you feel the difference yourself you’ll enjoy the benefits to your health & wellbeing!

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