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  • Jessie Brennan, MPH

Self-Care for Leaders: The Importance of Sleep

As a leader, what’s your most valuable resource?

There are so many ways this could be answered, and of course there is no wrong answer, as it stems from your experience. Many leaders would say their time is their most valuable resource. Others would say their teams are. Others, still, might say data is their most valuable resource, or the customer is their most valuable resource.

What about as a person- as a human existing on this earth, what is your most valuable resource?

I googled this question to get an idea of what the popular opinion was, and it appears that the consensus on the internet is that time is a person’s most precious and valuable resource. For me, the answer would be energy. Sure, time is something you can’t get back and can’t get more of, but without energy what can you really do with it?

Unlike time, there are certain things that we can do to get more energy- namely engage in self-care. Proper nutrition, a habit of exercise, rest, all of these will give you more energy, but nothing will consistently affect your energy more than healthy sleep habits. Sleep is critical for both health and productivity. It’s where we get our energy and focus, and it’s where you can develop your competitive edge as a professional.

Despite this being common knowledge, two-thirds of all people in developed countries do not get enough sleep. In fact, it’s such a problem that the American Centers for Disease Control and Prevention and the World Health Organization have both declared sleep loss a public health epidemic. But exactly how much sleep is considered “not enough sleep?”

The scientific community defines “habitual short sleep duration” as anything less than 7 hours a night. That means 7 hours is the absolute minimum we should be sleeping. As a parent to an infant, I found this definition a little disturbing. To make matters worse, according to sleep researchers, sleep debt is additive. One week of six hours of sleep per night is just as bad as a single night with no sleep at all. While most of us would consider a few sleepless nights to be harmless, the consequences are much more significant than we may realize.

Sleep is categorized into several different phases; the two primary phases being REM and deep sleep. During deep sleep our brain moves stored information from short term memory to long-term memory. REM sleep allows us to reinforce new memories and motor skills by replaying them in our dreams. Sleep is really the backbone of learning. Sleep before learning moves existing memories out of the hippocampus into the cortex, freeing up space for new information. Sleep after learning consolidates the new material, effectively hitting the save button.

The memory isn’t the only thing that suffers from sleep deprivation. On too little sleep our cardiovascular health takes a hit. In fact, hospitals report almost 25% more heart attacks the day after countries switch to daylight savings time and people lose an hour of sleep. Neglecting sleep suppresses our immune system, reducing the amount of cancer fighting cells in the body after just one night of short sleep. Regularly sleeping only 6 hours increases cancer risk by 40%.

The effects are emotional as well. With little sleep, rational control from our prefrontal cortex dims down, and the amygdala takes over, which can lead to inappropriate emotional reactions like anger or reactivity. Our emotions amplify- both the good and the bad, resulting in mood swings and risky behavior. This makes it difficult to stay calm in the face of difficult challenges, as an effective leader should. This overactive amygdala can lead to higher heart rates and blood pressure, anxiety attacks, and breathlessness.

Sleep acts like housekeeping for the brain. During sleep, brain cells shrink by 60%, allowing cerebrospinal fluid to rush through and flush out toxins like amyloid beta, a protein whose accumulation is the leading cause of Alzheimer’s disease. By getting sleep you’re actively keeping your brain healthy and young.

In short, you can’t lead amazing teams or solve big challenges if you are sick, your brain is foggy, and you’re riddled with stress. Luckily there is an easy solution: sleep more! A solid sleep routine will get you well on your way towards thinking and feeling better. The most critical first step is simply making enough time for sleep, by scheduling an eight-hour window every night. Sounds simple, doesn’t it?

And it is…for some. For others, setting aside 8 hours to sleep does not mean that sleep will come. Self-diagnosed insomnia is widespread, and while some do truly suffer from real insomnia, for most of us, our sleeplessness is a result of our behaviors. Here are a few factors to consider as you seek to address your sleepless nights:


Adenosine is a chemical that contributes to what is commonly referred to as “sleep pressure.” As adenosine builds in the brain, we feel sleepier and sleepier. The chemical is then cleared as we sleep. Caffeine works to block adenosine, preventing it from signaling to our bodies that we are tired, which is the effect we’re looking for when we consume caffeine. Right?

The problem is that caffeine stays in our systems much longer than most of us know. The half-life of caffeine in our bodies is roughly 5 to 6 hours, meaning if you have a cup at noon, a quarter of that caffeine will still be in your blood at midnight. Imagine my surprise as I read this data at 4:00 PM, coffee in hand. Who am I to tell you to cut caffeine or even limit your intake? I, for one, don’t want to live a coffee-less life, but it would pay for all of us to be conscious of our intake, and when we choose to have our last coffee, it may be impacting our sleep more than we know.


Alcohol is another somewhat misunderstood substance, in that many people believe that alcohol helps with sleep. This misconception comes from the fact that alcohol speeds up the onset of sleep, but it severely damages the quality of our sleep by causing frequent wake-ups (which we may not remember the next day) and suppressing REM sleep. You’ve probably had the experience of waking up the morning after imbibing and feeling like you hadn’t slept a wink, despite logging in as many hours as you typically would. Even just a small amount of alcohol negatively impacts all the positive effects of sleep, so avoiding alcohol around bedtime will do a lot to optimize your sleep.


Temperature may be the most under-appreciated factor in high-quality sleep. Studies have shown that a rapid decline in core body temperature increases the likelihood of sleep initiation, something that may be difficult to achieve in a warm bedroom under blankets. Experts recommend keeping the bedroom between 59- and 66-degrees Fahrenheit.

As odd as it sounds, a warm bath or shower may help cool you down as well. Warm water draws blood to the surface of your body, allowing your core to cool down and ushering in a faster and deeper sleep.


As wonderful an invention as the electric lightbulb is, it sure has wreaked havoc on our circadian rhythm. Rather than living in bright sunlight during the day and darkness at night, we envelope ourselves in dim indoor lighting for most of our waking hours. This keeps us sluggish in the morning, and prevents proper initiation of sleep in the evening. To get better sleep at night, try to get as much natural sunlight as you can early in the day, and keep the lights as dim as possible closer to bedtime. I’m sure you already know this, but the blue light that emits from our devices signals to the body that it is the middle of day. In order to get that melatonin necessary to get yourself ready for sleep, it’s best to avoid screens as much as possible before bedtime.

Our nightly sleep cycles are efficient mechanisms that optimize our mental stability and performance, and empower us to be the great leaders we aspire to be. Let’s celebrate sleep for what it is- one of the most amazing things our body is able to do! From physical and mental healing, to idea incubation and problem-solving breakthroughs, if the effects of sleep could be bottled, it’d be considered a miracle drug. Don’t get caught up in the frenetic busyness of life and forget the importance of sleep on your health and ability to lead.

Sweet dreams!

Jessie Brennan


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