Most people underestimate the impact of poor sleep.
They push through it.
They normalise it.
They assume it is just part of a busy life.
But even one or two nights of poor sleep can have a profound effect on how you think, feel and perform.
In this episode of Stay at the Top, I break down three ways poor sleep is quietly showing up in your day to day life, from your food choices to your emotional regulation to your immune system.
This is not about long term risk. It is about what is happening right now and why it matters.
If you are feeling flat, craving more, reacting more or getting sick more often, this episode will help you connect the dots and understand why sleep is one of the highest leverage behaviours you can focus on.
In this episode I share:
- Why even one or two nights of poor sleep impacts performance
- The link between sleep, appetite hormones and overeating
- Why poor sleep increases cravings for highly palatable foods
- How sleep deprivation affects decision making and willpower
- The impact of poor sleep on emotional regulation and reactivity
- The connection between sleep and immune function
- Research showing increased risk of illness with reduced sleep
- Why poor sleep often shows up during high stress periods
- How sleep influences energy, focus and daily behaviours
- A simple way to assess and track your sleep
Key Quotes
“This is not a willpower problem. This is a biological shift.”
“Even one or two nights of poor sleep can change how you eat, think and feel.”
“Sleep is one of the highest leverage behaviours for performance.”
Episode Resources
📖 PRE-ORDER For the Long Run by Jess Spendlove 👉 https://amzn.to/4t33BPh
Jessica Spendlove Website – www.jessicaspendlove.com
Jessica Spendlove Keynotes – JessicaspendloveKeynotes – Jessica Spendlove
The High-Performance Profile Quiz https://jessicaspendlove.com/quiz/
Jess Spendlove Instagram https://www.instagram.com/jess_spendlove_dietitian/?hl=en
Jess Spendlove LinkedIn https://www.linkedin.com/in/jessica-spendlove-64173bb8/
About Your Host
Jessica Spendlove | Wellbeing Speaker & High Performance Strategist
Jess Spendlove is an international wellbeing and high performance speaker, coach, and advisor. With over 15 years of experience across corporate leadership, elite sport and the military she is known for helping ambitious leaders and teams optimise energy, build resilience, and sustain peak performance.
As one of Australia’s leading performance dietitians and a trusted voice in executive wellbeing, Jess delivers science-backed strategies that empower individuals, teams and organisations to thrive under pressure and achieve long-term success.
Episode Transcript
The following transcript has been automatically generated and not checked for accuracy
Jess Spendlove (00:00.12)
More than 60 % of Australians are having issues falling asleep or staying asleep. That’s a pretty alarming statistic. Now, if we bring that back to how even one or two nights of poor sleep can impact you, the knock-on effects are profound. Today’s episode is looking at three ways that can show up. The first being you are more likely to overeat. We talk about the biological reason this happens. This isn’t just willpower. This is physiologically how your body reacts.
to having one or two nights of poor sleep. This can also show up in your emotional regulation and your decision-making ability. And it can also negatively impact your immune function. And how that shows up is getting sick more often. This episode is about bringing it back to how and why sleep is so important. The knock-on effects of getting poor sleep is profound. And how that’s showing up for you, like it is for a lot of people, is in the daily habits that you’re making.
The fact is when you prioritise sleep, when you find a way to get the quality and quantity that you need and the upstream effects, how that ripples into so many other areas of your life, like your energy, your food choices, your decision making, your emotional capacity is huge. So on that note, let’s get into today’s episode.
Today I want to talk about three knock-on effects of poor sleep. Now these are things that are impacting your every single day and they’re probably things that you’re not even actually consciously aware of. Now there are some pretty terrifying stats around poor sleep and what that can show up as from a long-term perspective. Chronic disease, certain metabolic conditions and cognitive decline, Alzheimer’s dementia.
We’re not gonna be talking about that scary stuff today, but that is something for you to be aware of. What I wanna bring it back to is how is poor sleep impacting you every single day? Now, the first place I wanna start is with one of my favourite things to talk about, which is the nutrition and sleep connection. Even getting one or two poor nights sleep, and how that is defined is less than six hours, actually increases your desire to eat.
Jess Spendlove (02:14.838)
Now that’s not going to show up as you needing to sit down to an extra meal. How that’s going to show up is what you were reaching for. By getting less than four or five hours sleep for one or two nights, research has shown that people are likely to overeat by 600 calories. Now 600 calories is huge. For a lot of people, that’s probably a third or a quarter of their intake.
And like I said, this isn’t you necessarily sitting down and thinking, I need an extra meal. It’s just what you are reaching for each day. Now, the reason that you are reaching for these foods is because your appetite hormones are dysregulated. Now there are two appetite hormones for you to be particularly aware of. We’ve got ghrelin and we’ve got leptin. When we are not getting adequate sleep, so when we’re getting less than six hours, ghrelin, which is our hunger hormone is up.
and leptin, which is our appetite suppression hormone, is down. So biologically, what is going on is you are being driven to want to eat more. On top of the disruption to these appetite hormones, there are changes to your brain chemistry. The rational part of your brain, the prefrontal cortex, isn’t able to operate like it typically does. So not only are you hungrier,
your ghrelin is up, you’re reaching for more foods, that ability to have willpower or make those decisions is also reduced. So this isn’t a willpower problem, this is a biological shift in how you are wired, simply because you haven’t had enough sleep. What I’m talking about here is one or two nights. Now most of us are susceptible to having one or two nights of poor sleep.
I know I’m definitely in that phase myself with a 16 month old, but even if you don’t have children, it might be because you had a busy weekend or you had a few drinks or maybe you’re on a deadline. Maybe you can’t wind down. Maybe you’re awake at two or three AM. And all of a sudden getting your seven, eight, whatever it is that you need is significantly reduced. This is one or two nights. Imagine how this compounds.
Jess Spendlove (04:33.536)
Imagine how this shows up if this goes on for a few nights or a week or a month or imagine if this is just something that you’ve actually subscribed to as this is just how I operate. I can function on less sleep. I’ve accepted that and that is how you’re operating. And so how this might show up for you is that craving which pops up. Now we’ve all got that one craving. For me, it’s chocolate.
Now, if I’ve got a regular chocolate craving in the afternoon or after dinner, that’s where I go, what’s happened? Have I missed protein or have I missed fiber or have I missed a meal across the day or have I slept poorly? So for you, I really encourage you to think about, have I got cravings more often or am I finding that I’m just reaching for that thing? For me, it’s chocolate, for you, I don’t know, it might be salt and vinegar chips. I feel like that pops up a lot.
or it might be corn chips, or it might be Yochi or Messina or whatever it is for you, we’ve all got the thing, check in, is this happening more often? And could this be because I’m not getting enough sleep? It’s really important for you to understand that particularly with behaviours like sleep and nutrition, they are not separated, they are actually interconnected. And they both have the power to positively or negatively influence each other.
When we’re not getting enough sleep, we’re driven to want to eat more. And we’re driven to want to eat more of those tasty, salty, fatty, refined carbohydrate foods. And when we’re eating like that, we’re generally back-ending our day with more food, which then disrupts our sleep. So you can see how this chicken or egg situation happens. It really requires you to be very intentional to break that cycle.
And in my book for the long run, I really dive into these areas. I talk about them as individual rhythms and I give you ideas on how you can apply these principles to your life. Particularly with nutrition and sleep, I cover of how interconnected they are. But the great thing about that, you can learn how to leverage them both to improve the other and you can watch out for the blind spots and how they might be unraveling and showing up in your day at the moment.
Jess Spendlove (06:50.742)
The second way that poor sleep can show up, and this is one that you’re probably familiar with, is your emotional regulation and your decision making. So what I’m talking about here is how snappy you are, or that road rage that might pop up, or that frustration that you get at a team member or maybe a partner because they…
left their dishes or their cups in the sink or whatever that might be. I think a lot of the time people put down to being more irritable or being more snappy or not able to regulate their emotions to everything else going on in their life. They might have a project or a deadline or stress or they might have a lot happening at home. So often it can be really easy to overlook what is happening with our sleep. But similar to the food point, even just one or two nights of poor sleep.
And when I’m talking about poor sleep, I’m generally referencing less than six hours. So even less than six hours for one or two nights can disrupt this. You can become more reactive, more irritable, less able to regulate. And then if this goes on for a week, which can be really common, particularly when you’re under stress in the office, it can be so easy to be ruminating and overthinking on this at night. And all of a sudden a week has gone by and you’ve been averaging four or five hours a night.
And as I said, this might not show up as you going to bed for that amount of time, but it might be the result of broken sleep or being awake at night, particularly that two to 3 a.m., which so many people report, particularly high performers and people with high cognitive load. If you haven’t had opportunities across the day to down regulate, if you don’t have a wind down routine where you can actually get pen to paper or get those thoughts out, if you haven’t processed that across the day,
Of course, in the middle of the night, that’s where we think about it. Now I’ve got a really exciting guest episode next week with Dr. Gemma King, where she talks about this in detail. She has her first book, Coming Out Sleep First, and she’s got some amazing theories that are science-backed from all her work with elite athletes, special forces, Fortune 500 CEOs, basically every single person operating in a high pressure environment. That’s definitely an episode to check out when it comes out next week. So if you’re showing up in a way that
Jess Spendlove (09:05.78)
you don’t like. And this is something that I’ve had to reflect on, particularly over these last 16 months, navigating this new season of motherhood and running a business. If you’re showing up in a way that you don’t want to, if you’re feeling more irritable, if you’re less patient with your family, potentially you’re catastrophizing or overthinking or ruminating on problems. First of all, probably be kinder to yourself. I know for myself when I’m showing up like this and I’m aware of it.
that inner critic is particularly harsh, but I also know that isn’t actually who I am. And after doing this work and teaching this work and relearning this work so many times, it’s something I’m still working on being kinder to myself, but I now know this is my number one red flag on what my sleep is like.
And for me, I do use a wearable. I’ve got my work band on, so I have that data. If you don’t use a wearable, if you don’t want to use a wearable, that is totally fine. Potentially what you can do is just keep a little bit of a record, maybe in your journal, maybe in your phone. That can be the time you go to sleep, the time you wake up, what your energy levels are like. And maybe also taking note if you’ve been awake at night. If this is an area that you do want to improve on, I am really pro.
using a wearable of some sort. It just helps add some objective data to the situation. Doesn’t have to be something that you use forever. You can use it for a period of time. I guess the thing to be mindful of is how you’re wired. And so if you’re someone who that is going to create more stress, more pressure, maybe don’t. But if you’re someone who can view it as a tool, as something that can help support you.
The great thing is when something improves like your sleep, it’s kind of like getting a little pat on the back. And it also does give you feedback in real time and some cues and some strategies and it helps you get the data. I personally find it really helpful. A lot of my clients do, but you need to decide if that’s something that’s right and helpful for you. But for you to win the day, if that’s something you subscribe to, and if you hate that saying, maybe it’s not win the day. But if you just want to show up with more energy,
Jess Spendlove (11:19.7)
more emotionally regulated, clearer thinking, that really starts with winning the night first. And winning the night is about the quality of sleep, the quantity of sleep. Because when you get that right, everything shifts. And the third way that poor sleep might be showing up for you is with your immune function. So if you’re someone that feels that you get sick often or every winter, you you’re picking up anything that’s around.
then this might actually be getting driven by the fact that your sleep is not adequate. In last week’s episode with Dr. Cecilia Kittik, we focused on the immune system and the role of the microbiome. She also mentioned some research which I wasn’t actually aware of before she touched on it, but I wanted to bring it to this episode because I really wanted to emphasize it. And also if you haven’t listened to that episode, I wanted to make sure that it was clear because I see a lot of people
particularly people in high-power jobs, working long hours, potentially with a family or maybe not. But when they are operating like that, there is some chronic stress happening and that can seep into how someone is sleeping. The first piece of research that I wanted to call out was done in 2009 and it was 153 healthy men and women and they tracked how they slept over a two week.
period. At the end of that period of time, they were then exposed to a common virus. So rhinovirus, which is a typical cold and flu. They had ethics to do this. I realized listening to it, you might be thinking what is actually going on, but it was well approved. And what they found that people who were sleeping less than seven hours were nearly three times more likely to get sick than people sleeping more than seven hours.
That’s a pretty significant statistic. The same group of researchers then in 2015 replicated the study, but this time they used trackers. And in that they looked at different time points of sleep. And they found that people sleeping under five hours were four and a half times more likely to get sick. So we can start to see this connection with how long we’re sleeping, the quality of our sleep.
Jess Spendlove (13:36.66)
and our immune function. In this second piece of research, what they found is that sleep outranked any other factor when it came to immune function. It outranked age, stress, income, smoking, and exercise as a risk factor. Now stress and sleep are interesting. find a lot of the time they often go hand in hand, but the point is sleep and not getting enough sleep
puts your immune system under huge strain. And this is one of those areas that doesn’t necessarily show up straight away. Potentially you’ve had some poor sleep here or there, maybe it’s gone on for a period of time. Right now we’re coming, well, we’re not coming into autumn, we are in autumn, but we’re in autumn getting closer to winter. This is when the bugs and the germs and everything increase. And so if you’re not getting enough sleep, plus this time of year,
plus you potentially have unmanaged stress, this is definitely increasing your risk of getting sick. And I don’t know about you, but this is definitely something which I’ve been impacted with previously. There was a period of time where I operated full throttle. I thought I was invincible. I thought that I had a greater capacity than anybody else. I was working six or seven days a week, 10, 12, 14 hour days, traveling around the country with different sports teams.
complete workaholic, yet there I was being paid to help athletes with their nutrition and their recovery and their sleep. And yet I thought the science and the evidence and the way I was helping them didn’t apply to myself. And the way this always showed up for me was getting sick. It wasn’t big illnesses or anything at the start. It was just the colds, the flus, know, getting sick at the absolute worst time.
I want you to have a think, does that happen to you? Do you tend to get sick either right before or right after a big project or a presentation or a deadline, or potentially it’s not even work related, maybe it’s life related? Do you go on holidays and one or two days into that holiday, that’s when you get sick? All of these are red flags in terms of how you’re operating. And I want you to then reflect on what is happening with my sleep. Are you just accepting that poor sleep is how you operate?
Jess Spendlove (15:55.746)
Have you subscribed to the fact that you don’t need that much sleep? If this is a narrative that’s going on, I really hope this episode helps you question that or helps you identify how poor sleep might actually be showing up for you, because it can be really easy to just push through, have all of the excuses, have all of the commitments, but the truth is you prioritize what is important. And the way I see sleep is really it’s probably the highest leverage point behavior.
because when your sleep is improved, your energy is improved. The food choices you’re making is improved. Your mental clarity is improved. You’re more emotionally regulated. You’re also less likely getting sick. The knock-on effect of all of this is huge. And so the reason why sleep is such a high leverage point behaviour is because when this improves, everything else gets easier.
You’re not having to fight against willpower or exhaustion or cravings or anything else. You’re not having to push through. All of this just operates in more rhythm. And so if your pattern sounds like pushing harder, cutting sleep, getting sick in the moment either before or the moment you stop, I really think this is something to reflect on. And if you haven’t already listened to last week’s episode with Dr. Cecilia,
I highly recommend you go back and listen to that because we dive much deeper on this third point. In my book For the Long Run, which is now available for pre-order, there will be a link in the show notes if you want to go and check it out, but sleep has its own dedicated chapter. Now, sleep is one of the biggest and most important forms of recovery, but there are so many knock-on effects to what happens when you sleep well or when your sleep is jeopardised. Some of that we’ve covered in today’s episode. I dive a lot deeper in the book.
So if you haven’t already ordered it, it is available for pre-sale now. But just to recap on the action point for today’s episode. So if this is speaking to you, if you think, yeah, I need or want to sleep better, I want to prioritise my sleep, I can see how this might be showing up for me. The action point for you to take is to take stock for seven days. How are you sleeping?
Jess Spendlove (18:08.258)
You know, write it down as I mentioned in your journal or in your phone, or if you use a wearable, you can track it that way. But if you don’t want to use a wearable, either of those other ways are fine. And it’s really about taking stock. What time do I go to bed? What time do I wake up? How am I feeling across the day? And when I wake up, am I waking in the middle of the night? And if so, for how long? If you actually capture what you’re doing, that is the first step in becoming more self-aware. And that
is a really critical point if you want to improve your behaviour. The reason sleep is so fundamental, and I want to say this again, is because the knock-on effect into every other area of your life is profound. From what you eat to how you move to your immune function to how you think across the day to how you show up at work or with your family. So rather than focusing on all of that, if you just focus on sleep, if you prioritise it.
If you aim to be more consistent with it and you get the best quality sleep that you can, that is going to ripple into every other area of your life in such a positive way. That brings us to the end of today’s episode. If you haven’t already subscribed, make sure you do. You won’t miss one that’s coming out.
And if you know someone who would benefit from listening to this episode, it would mean so much for me for you to share it with them, tag them, however you communicate, however they like to consume their podcasts, because I know that there are so many people out there who are sleep deprived, who are not getting enough sleep, and the way that will impact them and how they show up is absolutely profound. Thank you for joining me for my first solo episode.
fully recorded. I’m looking forward to being back next week with Dr. Gemma King for her guest episode where we dive deeper on sleep and why you need to put sleep first. Otherwise, I will see you then and I can’t wait to help you not only reach the top, but sustainably stay there.