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What Causes Insomnia?

What keeps you up at night? Pondering deep questions? Excitement about a big trip? Or is it stressabout unfinished work, an upcoming test, or a dreaded family gathering? For many people, thisstress is temporary, as its cause is quickly resolved. But what if the very thing keeping you awake
was stress about losing sleep? This seemingly unsolvable loop is at the heart of insomnia, theworld’s most common sleep disorder.
Almost anything can cause the occasional restless night - a snoring partner, physical pain, oremotional distress. And extreme sleep deprivation like jetlag can throw off your biological clock,wreaking havoc on your sleep schedule. But in most cases, sleep deprivation is short-term.
Eventually, exhaustion catches up with all of us. However, some long-term conditions like
respiratory disorders, gastrointestinal problems, and many others can overpower fatigue. And as

What Causes Insomnia?

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sleepless nights pile up, the bedroom can start to carry associations of restless nights wracked withanxiety. Come bedtime, insomniacs are stressed. So stressed their brains hijack the stressresponse

system,flooding

thebodywith

fight-flight-or-freeze

chemicals.

Cortisolandadrenocorticotropic hormones course through the bloodstream, increasing heart rate and bloodpressure, and jolting the body into hyperarousal. In this condition, the brain is hunting for potential
threats, making it impossible to ignore any slight discomfort or nighttime noise. And wheninsomniacs finally do fall asleep, the quality of their rest is compromised.
Our brain’s primary source of energy is cerebral glucose, and in healthy sleep, our metabolism
slows to conserve this glucose for waking hours. But PET studies show the adrenaline that prevents
sleep for insomniacs also speeds up their metabolisms. While they sleep, their bodies are working
overtime, burning through the brain’s supply of energy-giving glucose. This symptom of poor sleep
leaves insomniacs waking in a state of exhaustion, confusion, and stress, which starts the process
all over again. When these cycles of stress and restlessness last several months, they’re diagnosed
as chronic insomnia. And while insomnia rarely leads to death, its chemical mechanisms are similar
to anxiety attacks found in those experiencing depression and anxiety. So suffering from any one ofthese conditions increases your risk of experiencing the other two.
Fortunately, there are ways to break the cycle of sleeplessness. Managing the stress that leads tohyperarousal is one of our best-understood treatments for insomnia, and good sleep practices canhelp rebuild your relationship with bedtime. Make sure your bedroom is dark and comfortably cool tominimize “threats” during hyperarousal. Only use your bed for sleeping, and if you’re restless, leave
the room and tire yourself out with relaxing activities like reading, meditating, or journaling. Regulate
your metabolism by setting consistent resting and waking times to help orient your body’s biologicalTedEd-22

What Causes Insomnia?

clock. This clock, or circadian rhythm, is also sensitive to light, so avoid bright lights at night to help
tell your body that it’s time for sleep. In addition to these practices, some doctors prescribe
medication to aid sleep, but there aren’t reliable medications that help in all cases. And over-thecounter sleeping pills can be highly addictive, leading to withdrawal that worsens symptoms. But
before seeking any treatment, make sure your sleeplessness is actually due to insomnia.
Approximately 8% of patients diagnosed with chronic insomnia are actually suffering from a lesscommon genetic problem called delayed sleep phase disorder, or DSPD. People with DSPD have acircadian rhythm significantly longer than 24 hours, putting their sleeping habits out of sync withtraditional sleeping hours. So while they have difficulty falling asleep at a typical bedtime, it’s notdue to increase stress. And given the opportunity, they can sleep comfortably on their own delayedschedule.
Our sleeping and waking cycle is a delicate balance, and one that’s vital to maintain for our physicaland mental wellbeing. For all these reasons, it’s worth putting in some time and effort to sustain astable bedtime routine, but try not to lose any sleep over it.