Everyone talks about diet and exercise for dropping kilos, but do you know about the relationship between sleep and weight loss?

Even if your nutrition and workout plan is bang-on, you will struggle to lose weight if your sleep is off-track. Let’s take a look at the links between sleep and weight loss and how you can use them to your advantage.

The key relationships between sleep and weight loss

The human body is pretty complex, and every system relies on getting plenty of quality rest. But there are a few critical links that we need to explore between sleep and weight loss.


The biggest baddy when it comes to your sleep sabotaging your weight has to be stress. Sleep deprivation is a massive source of physical stress on the body because you don’t get the chance to restore and repair tissue damage.

Elevated cortisol levels can tell your body to store more body fat to protect you. It also encourages the use of muscle as an energy source, leading to a lower metabolic rate. And in terms of your appetite, cortisol will boost it and encourage you to eat more food overall.

What does this mean for your weight loss efforts? Well, one study found that in people attempting weight loss, participants who got 5.5hrs of sleep per night lost 60% more muscle mass compared to those who got 8.5hrs of sleep. The sleep deprivation group also experienced 55% less fat loss.

That means not only did they lose less fat – but they also sabotaged their metabolic rate long-term by losing muscle mass!

Insulin resistance

Another big link between sleep and weight loss is your insulin sensitivity/resistance. When you are more resistant to insulin, your cells can’t access the energy (sugars) they need to function properly.

As a result, the body will convert more energy into fat stores, rather than using it for fuel. It will also cling to those fat stores and avoid using it for energy as much as possible! Oh and just for good measure, it will also make you crave more sweet, carb-dense foods because your cells still need that energy.

Now here is the scary bit – just one night of partial sleep deprivation can induce insulin resistance. That’s part of the reason why you crave unhealthy foods after staying up too late! Long-term sleep deprivation can contribute to ongoing insulin resistance and even lead to type 2 diabetes.

Thyroid function

If that wasn’t enough, we also have to consider how sleep deprivation can affect your thyroid. As you might know, your thyroid is like the engine of your metabolism. If it’s not working optimally, weight loss becomes an uphill battle.

Acute sleep deprivation – aka missing one night – does not have a huge effect on your thyroid. But when researchers looked at 14 days of partial sleep deprivation (5.5hrs per night), they found thyroid function was impacted. Thyroid-stimulating hormone (TSH) and T4 (thyroid hormone) levels actually dropped, particularly in female participants.

If just 2 weeks of skimping on sleep can do that, imagine what months or even years could do!

And just to make things more difficult? Thyroid function is also interlinked with stress and insulin resistance. So once one factor goes out of whack, the rest are soon to follow.

How to sleep if you want to lose weight ASAP

So now you know why sleep and weight loss go hand in hand. But how do you implement this knowledge so you can release those excess kilos?

First up, we need to remember that sleep is one of the puzzle pieces. If you’re not moving, eating plenty of nourishing wholefoods or managing your stress, getting some zzzs won’t make 10kg vanish magically overnight!

But if you do want to set up your sleep so you can find your body’s happy weight, you need to:

Sleep enough hours – that means 7-9 hours for most people. If you are incredibly busy, physically active and/or juggling an underlying health condition, there’s a good chance it’s closer to 9hrs. Sorry, I don’t make the rules!

Sleep the right hours – they say ‘an hour of sleep before midnight is worth two hours after’ for good reason! In fact, research even shows that early to bed can help you to live longer compared to those who stay up late. You want to get a couple of sleep cycles in before cortisol starts to rise around 2am. I recommend my clients are asleep by 10.30 most nights of the week. If you can, the early, the better!

Sleep deeply – if you get 8 hours of sleep and are in bed by 10, but you toss and turn or wake up multiple times? We need to get to work on your sleep quality. If your sleep quality is MIA, make sure you check out this article for actionable tips to get better sleep during perimenopause.

Sleep is one part of the equation – so how do you get all your ducks in a row and drop some excess weight?

It might seem like a lot to tick off if you want to lose weight, but there are ways we can streamline your health so everything works together.

Book in for a free discovery call today, and we can explore how I can help you to release unwanted weight and feel amazing in your own skin again.