How lack of sleep impacts your weight and brain health

Sleep is one of the easiest things to give up when you’re busy, you just go to bed late. Right? It’s not so easy to wake up early but it’s easy to go to bed late and sacrifice sleep to finish things from the day.

The problem is: This can affect so much in your body especially your brain and your weight.            

Science links poor sleep to a host of health concerns such as weight gain and cardiovascular health. But in recent research the impact on brain, mood, and cognitive function clearly stands out.

Sleep actually effects every system in your body. 

In this article, I outline:

1. The impact of poor sleep on weight and your eating behaviour and food cravings
2. The impact of poor sleep on your brain and cognitive function 
3. What helps you to sleep better + a quick circadian reset

When you disrupt your sleep, it’s going to affect things like your skin, how clearly you can think, your brain’s ability to deep-clean for your mental clarity, your stress, your immune system, your metabolism and how quickly or slowly your metabolism runs.

Sleep even affects our genes. There was a study done in 2013 in the UK that showed that sleep can affect 711 of your genes!

Some of these genes are the ones that relate to infection, stress, inflammation – and so it’s really important that you don’t impact those genes negatively. You will find yourself sick and you can’t do the work that you want to do and you can’t be productive. 

1. The impact of sleep on hormones and eating

Sleep affects your hunger hormones

Sleep affects different hunger hormones for men and women.

For men, sleep affects your ghrelin hormone which stimulates your appetite.

For women, it affects GLP-1 – appetite suppressing hormone.

The result is the same for men and women – you will eat more and your appetite increases but for the bad foods.

You won't crave nutritious natural foods with ‘subtle’ more natural tastes and flavours that are good for your body and your brain.

This shows how different men and women are and how sleep is really complicated and why it’s so vital for us.

It’s not as simple as, ‘If I can’t get sleep, I will just push through’ – there is serious biochemistry that happens when we have enough sleep and when we don’t have enough.

Hormonal imbalance

In general, a lack of sleep will result in a plunge of a hormone called the leptin.

Leptin influences all other hormones in your brain. It coordinates our inflammatory response and it will help determine whether we crave carbs and sweet foods or not.

When you’re tired, you will crave carbs and sweet things and just more food in general, which is totally normal because our hormones are making us feel that way.

Don’t just think that you’ve got no will-power. It’s pretty hard to have will-power when you haven’t had enough sleep because your body literally can’t function properly without sleep.

The studies show that increase in ghrelin is correlated with wanting to eat bad foods, fatty foods (bad fat not avocadoes!), junk food, heavy oily foods like burgers, chips, fast food

In general – you will want to eat lower nutrient foods and bad carbs

This is what your brain is craving and it’s what your brain is telling you from the hormone it’s secreting. 

Bad eating behaviour/food cravings

When your hormone levels are out of balance and not behaving properly your brain becomes disconnected from your stomach and this results in your brain making you think you’re hungry when you’re not actually hungry.

And that’s when people will eat the bad foods and overeat and snack throughout the day, because they are lethargic and feel low in energy and think that they need that boost from food, when actually they just need a proper night sleep or a nap.

Most importantly when you’re sleep deprived, no matter how much will-power you think you have – it’s fundamental that you understand what’s happening in your body.

There is no way that you can control this – will-power is not enough to get you through these cravings when you’re tired. The only way you can control this is by getting enough sleep.

It’s much harder to resist those foods – fast carbs, sweets, cookies and chocolate – when you’re sleep deprived.

Research shows that your resting metabolism rate decreases with sleep deprivation. Which is what your metabolism is when you’re not doing anything eg. watching TV or reading.

So, having adequate sleep will also increase your resting metabolism rate so you’re burning more fat, whilst doing nothing. If that’s affected, you will gain weight.

Research also shows that not having enough sleep can increase the risk of having insulin resistance. When your cells become insulin resistant – more sugar remains in your blood stream and then the body has to produce more insulin to compensate this. The excess insulin then tells your body to store these excess calories as fat. 

2. The impact of poor sleep on the brain and cognitive function 

New research is beginning to understand cognitive decline that can happen after years of poor sleep. Addressing these issues early may be key to optimal cognitive health as we age.

Studies link sleep concerns to poor drainage of newly discovered brain lymphatics, called glymphatics, which dump around 1.4kg of toxins, plaque, and waste out of the brain each year while you sleep.

Cerebral spinal fluid is basically lymphatic fluid inside the spinal column and brain that acts like a brain-washer, flushing toxins while you sleep!

This process comes to a halt during the day and it is only active at night during sleep. And so poor sleep is linked t a build-up of brain toxins in the glymphatic system.

It’s so important to get a good night sleep – because sleep cleans the brain. This is related to the state of your sinuses and your immune system.           

Circadian sleep

The brain draining waste during the night when we sleep is part of our circadian rhythm. We can’t affect when it’s done, it’s out of our control. The only thing we can do is get in sync with this rhythm by sleeping at certain hours at night.

What’s important is the deep sleep during the REM hours – that’s why between 10-12pm you need to be asleep because if you’re not asleep during these hours – the toxins build up in the brain. You can’t get the same quality of sleep after midnight.

 If you find that you are wanting to wake up earlier but don’t go to bed past midnight, it just messes up with your circadian body clock, your hormones, and your whole body.

Get to bed as early as possible, read a book to unwind, create a night time routine that’s flexible but just to help your body get ready for sleep is really important.           

3. What helps you to sleep better - a quick circadian reset

• Go to bed by 10pm at least 4 nights a week, and to reset 4 nights in a row. Wake up early to get your work done if you have it left from the day before.
• Cooler body temperature, so don’t sleep in thermals or several layers and drop the room temperature with a flow of air even in the winter for cool air circulation
• Eat early dinner so you body has had a chance to do the initial stage of digesting – this takes 2-3 hours after eating. Only then can your body go into the repair and restore mode.
• Turn of your devices and separate yourself from them – leave them far away from your bedroom.
• Exercise in the day as that helps to move the lymphatic system, which makes way for glymphatic detox at night.

Conclusions

Sleep is so much more complicated than just, 'if I sleep, I’m not tired - if I don’t sleep, I’m tired.'

It can affect so many of your bodily functions. I touched the insulin resistance and weight gain.

But more importantly, it also affects your brain, your mental capacity, your immune system as you are more likely to get sick if you are sleep deprived.

Let me know: What are your thoughts on getting your sleep in order? Share in the comments below and like the article if you found it helpful.

Katarina x

Katarina Hunter | Holistic Women's Coach and Founder of Stress Smarter? System - Holistic Health Regeneration for Women

My research links:

https://www.scientificamerican.com/article/the-sleep-dementia-connection/

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1978319/

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3319648/

https://journals.physiology.org/doi/full/10.1152/japplphysiol.00660.2005

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3767932/

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4701627/

https://academic.oup.com/ajcn/article/95/4/818/4576711

https://pubmed.ncbi.nlm.nih.gov/16880772/