Getting a good night’s sleep has many positive health benefits, from repairing your DNA and increasing your antioxidants, to slowing the ageing process.
But do our genes actually dictate how well we sleep?
The short answer is yes, they will dictate as to whether you are a morning person or a night owl, the duration of sleep, if your sleep is fragmented and if stress will affect you sleeping well.
For instance, stress and sleep can be the perfect chicken and the egg scenario. Being continuously stressed will have a negative effect on your sleep quality and getting poor quality sleep will increase your stress levels.
Your health can be affected by a variety of factors, and one that is currently being studied is the effect of sleep and our circadian rhythm.
Our circadian rhythm is thought to regulate around 15-20% of our genome and is tremendously important to keeping us fit and healthy as it affects our hormones, eating habits and reduces the chances of us becoming ill.
Our diet also has huge connotations for how well we sleep. For instance, the “Sleep hormone” melatonin, which is responsible for signalling darkness to the body and regulating daily physiological rhythms, is dramatically affected by retinol (Vitamin A).
Studies have shown there are high levels of retinol (vitamin A) in the mammalian pineal gland and that vitamin A deficiency causes a reduction in gene AANAT, which will reduce melatonin levels.
There are a whole variety of health connotations associated with poor sleep quality. Below we will be briefly touching on a few of the main ones, to hopefully shine some light on the issue.
Firstly, an interesting study from the University of Chicago looked at individuals wishing to lose weight following a calorie-restricted diet at the same time as monitoring their sleep.
One group was sleep deprived, only gaining 5.5 hours sleep.
The other group on exactly the same diet but getting 8.5 hours sleep found that at the end of the study they’d lost 55% more body fat simply from sleeping more.
Now this goes against the modern-day dogma of doing more to achieve your goals and in many ways sounds counterintuitive, as how does doing less (i.e. sleeping) actually give you more in terms of burning fat.
Now this isn’t just a matter of sleeping more!
What actually happens whilst we sleep that enhances everything that we do, and becomes some kind of elixir to our health, fitness and longevity?
To explain, we’ll talk through a few hormones that may be having an effect on your sleep and health.
HGH, (Human Growth Hormone) is an extremely powerful hormone that you produce during the first part of your sleep cycle and helps to produce more lean muscle.
It’s also muscle sparing and helps to protect the muscle that you already have.
HGH also helps to increase energy levels and is known as the “Fountain of Youth” as you will have naturally higher levels during childhood.
Sleep is the key here, as you won’t increase your levels from a silly supplement that claims to “Increase HGH by 555%”, but you will increase levels by getting a good night’s sleep.
The second hormone that we need to look at is cortisol, which has become a bit of a buzzword and bogeyman of late.
Cortisol is responsible for a whole variety of metabolic functions such as helping to regulate your thyroid hormone.
The thyroid regulates nearly every major metabolic function in your body, and as such, a poor functioning thyroid can have a detrimental effect on nearly every area of your health.
For instance, weight gain, reduced metabolic rate, fatigue, feeling depressed or moody, dry hair and skin, and much more.
Cortisol is our friend for most of the time; it only becomes an issue if it’s produced at the wrong time and in the wrong amount.
Sleep deprivation has an immediate effect with an increase in cortisol levels and a decrease in HGH production.
So, if you’re staying up late, and burning the midnight oil or checking your emails then your cortisol levels will be through the roof, and you will literally be breaking down your muscle tissue for energy at an elevated rate.
This process is called gluconeogenesis, where you will be breaking down your valuable muscle tissue into sugar (glucose)
The next hormone in the sleep equation is melatonin, or the “Sleep hormone” as its been labelled of late.
Melatonin has been shown to have a great effect on fat loss, as it helps to increase Brown adipose tissue (BAT), which functions in many ways like muscle in regard to burning White adipose tissue (WAT)
Increasing your levels of BAT fat will help to increase your metabolic rate, with melatonin having a direct correlation to increasing your levels of BAT fat.
Then we have Leptin, which is your body’s satiety hormone (the hormone that makes you full)
An interesting study at Stanford University discovered that just one night of sleep deprivation and poor sleep quality leads to quite a severe suppression of your leptin levels.
This is one of the reasons that you will eat everything in sight following a late night, as your “feeling full” hormone isn’t firing on all cylinders.
Now the last hormone we will be looking at is Ghrelin, which is your body’s “hunger hormone”.
Another interesting study showed that just one night of poor-quality sleep led to a 20% increase in Ghrelin levels.
So again, this may be one reason as to why your appetite goes through the roof following a late night, or continually going to bed late.
During our sleep is when we repair damage to our DNA. One of the ways that this is done is by releasing one of our previously mentioned hormones “Melatonin” at night, which is inhibited by blue light during the day and our phones, laptops and tablets at night – and activates and regulates over 500 genes that are involved in repair and antioxidant function.
Sleeping is very important to repair a lot of the damage done during the day. It also activates the Glymphatic system, which is a complex network of blood vessels that extends from the spinal fluid all the way throughout the brain.
During our sleep we will actually release cerebral spinal fluid up into the brain to wash out all the cellular waste products that have built up during the day.
So, getting a good night’s sleep has many positive health connotations, from repairing your DNA and increasing your antioxidants to improving the length of your telomeres, which slow the aging process, and are mother nature’s stopwatch.