Why Can't I Sleep? Top Reasons for Insomnia

You probably already know that a good night’s rest is vital for health, but what if you just can’t sleep?

If so, you’re not alone--experts estimate 1 in 3 people have at least mild insomnia.

But the causes for poor sleep vary greatly, and the specific cause can help inform treatment.

This article will cover the most common causes of poor sleep and how you can remedy them. 

Most Common Causes of Poor Sleep

Insomnia and non-restorative sleep can have many sources; stress, environment, existing health conditions, and lifestyle are just a few things that can wreak havoc on our biology and therefore our ability to sleep. 

Specifically, here are the top poor sleep causes:

• High cortisol at bedtime 

• Low melatonin 

• Hormone fluctuations due to perimenopause & menopause

• Spiking blood sugar

• Circadian rhythm issues

Poor Sleep Can Cause a Myriad of Health Problems

In our modern-day fast-paced world, sleep is often pushed to the back burner. Some even value their productivity to the extent that lost sleep is considered a badge of honor. 

But the consequences of sleep loss can be dire to your health. 

Sleep loss can increase your risk of the following conditions: (1, 2)

• Heart disease

• Stroke

• Depression

• Weight gain/obesity

• Memory and attention problems

• Brain fog

Sleep loss can even affect your physical appearance: we’ve all probably had dark circles and bags under our eyes after a bad night’s sleep. So lack of sleep affects the way you look, too. 

In a 2016 study that looked at factors that aged the skin, participants with sleep loss looked “markedly less healthy, less attractive, and more tired.”(3)

You might be thinking that this only applies to workaholics or new moms, or people with chronic insomnia. Surely you’re okay if you only miss a few hours here and there? 

Maybe not--according to a 2016 study, it takes 4 days to fully recover from just one hour of lost sleep. (4)

Unpacking the Causes of Poor Sleep

It’s easy to blame stress or even anxiety for trouble sleeping, but what does “stress” really mean in terms of your biology, and can it be fixed? 

The good news is that finding the specific cause of your insomnia can lead to fixes that’ll have you slumbering peacefully in no time. From high cortisol to hot flashes, we’ll dive deeper into each of these reasons for poor sleep and how to remedy them!

1. High Cortisol Levels Can Result in Poor Sleep

Cortisol is a hormone with many jobs in the body, but one is to help regulate sleep. Its levels rise and fall on a 24-hour schedule that matches your natural circadian rhythm, and it works in balance with other hormones. When this balance gets disrupted, sleep problems can occur. Below are the top reasons for cortisol disruption.

High Cortisol Cause 1: Stress

Cortisol is probably best known as the “stress hormone,” for good reason: the body cranks out cortisol when we get stressed out. 

This is ostensibly a good thing; we need this to protect us from threats. When our ancestors roamed the plains and came upon a sabertooth tiger, the immediate release of cortisol and other hormones helped put their nervous systems into sympathetic or “fight or flight” mode: the heartbeat races, blood sugar spikes, and breathing becomes rapid, all preparing you to meet this threat.

Unfortunately, our present-day brains can’t differentiate modern-day stress (i.e., you’re late for an interview) from the prehistoric stress (the tiger), so it tells the body to respond in exactly the same way.

It might save your life on the savannah, but in the absence of real threats to our survival, there’s real consequences to triggering fight or flight mode as often as we do. 

It’s possible that our high-stress lifestyles mean almost constant high cortisol levels, making good sleep more difficult. 

And to make things worse, losing sleep can cause your body to produce even more cortisol, exacerbating the problem.

High Cortisol Cause 2: Infections

Stress isn’t the only cause of too much cortisol. Cortisol is released during the immune response and helps to control inflammation; therefore high cortisol can signal some types of infections.

2. Low Melatonin Can Result in Poor Sleep

It’s melatonin’s job to help regulate your circadian rhythm (your pattern of sleeping and waking). It’s highest in the body between 12-8 am, and overall levels of melatonin decrease as we age. 

If we don’t have enough of this hormone when we go to sleep, it can make it harder to fall and stay asleep.

Low Melatonin Cause 1: Blue Light Exposure

Melatonin production is regulated largely by light: when our eyes receive light, such as when we wake up, they send signals to the pineal gland to shut off the production of melatonin. When it gets darker, melatonin production ramps up to prepare the body for sleep. As a result, your circadian rhythm can be thrown off by 1) not enough light exposure during the day and 2) too much light in the evening (especially blue light exposure).

That’s right--if you’re using a screen in the evening, you could be programming your brain to stay awake.

Any screen--television, tablet, phone--is a light source; and since we tend to stick our faces right in front of them for long periods of time, they begin to have the power that previously only the sun was capable of: the power to alter your hormones and convince your brain that since it’s receiving light, it should keep you awake. 

Blue light is particularly good at tricking the brain and suppressing melatonin, especially after sundown. Why blue? The visible light spectrum that human eyes can detect is of course made up of the rainbow of colors; but not all colors radiate the same energy. Blue light is the most energetic part of the spectrum that we can see, so it packs more of a punch than red light does on the other end of the visible spectrum.

Harvard researchers reported that blue light has twice the effect on melatonin production as compared to green light, and found that limiting blue light exposure ameliorated these effects. (6)

Low Melatonin Cause 2: Pain/Discomfort

If you wake up in pain, it’s possible low melatonin could be the culprit. 

For sufferers of IBS, pain can often wake them up during the night and prevent good sleep. Studies have shown that IBS can be correlated with low melatonin, and melatonin supplementation has been suggested as a helpful treatment for IBS.(7) 

Restless Leg Syndrome can also cause symptoms that may not be described as pain, but rather unpleasant sensations, usually in the legs. It can cause the sufferer to feel as though they have to constantly move their legs to dispel the sensations, and often getting up and walking or pacing is the only way to get relief. 

Low Melatonin Cause 3: MARCoNS

Melatonin can also be low due to MARCoNS, or Multiple Antibiotic Resistant Coagulase Negative Staphylococci, a bacteria that can live in the nasal passages of people with mold exposure, Lyme disease, or other inflammatory diseases. 

For more information on MARCoNs and mold, see our article Do I Have Mold Toxicity?

3. Low Progesterone Can Result in Poor Sleep

Progesterone is an important hormone for female reproductive health, but having low levels of progesterone can also affect your sleep. 

Low Progesterone Cause 1: Menstrual Cycle

Even when hormone levels are normal, they can impact your ability to sleep. 

Progesterone’s main role is to help during pregnancy, and its levels change every week of a woman’s cycle. For the first two weeks, progesterone remains low. But during the third week following ovulation, progesterone spikes as it prepares the body for pregnancy. If no pregnancy follows, progesterone drops sharply.

Progesterone is known for being the “calming” of the female sex hormones; higher levels of progesterone generally have a sedating effect. Since progesterone is low for the first two weeks of a woman’s cycle, she may have a harder time sleeping during this period. 

Low Progesterone Cause 2: Menopause and Perimenopause

Of course there’s also menopause, perimenopause, and all of the hormonal upheavals they bring to the table. 

As women age, hormone levels decrease in general, but menopause can cause them to fluctuate wildly. Hot flashes, night sweats, and other menopause or perimenopause symptoms could leave you tossing and turning at night. 

Low Progesterone Cause 3: Liver Congestion

Even your liver can affect levels of progesterone! If your liver is congested, it can cause a condition called estrogen dominance in which the balance of estrogen to progesterone is tipped and your body doesn’t have enough progesterone to balance out the estrogen. 

When estrogen needs to be broken down and reprocessed, it’s sent to the liver. But if your liver isn’t healthy, estrogen doesn’t get broken down and returns to the bloodstream. 

For more information on cleaning out your liver, check out our blog on Foods That Support Liver Detox.

4. Blood Sugar Issues Can Result in Poor Sleep

If you eat a large meal or consume alcohol before bed, spiking blood sugar could be to blame for your inability to sleep or sleep well.

Blood Sugar Spike Cause 1: Late Night Eating

Experts have long recommended separating meals and bedtime by at least a few hours. Late night eating could have you wired instead of tired before bed, for one. 

Having a lot of food in your stomach and lying down is a recipe for GERD or acid reflux, which can wake you up from a sound sleep.

Also, processing a large meal means your kidneys are working hard to do their job, which is largely to generate urine; midnight trips to the bathroom aren’t conducive to a good night’s sleep.

Blood Sugar Spike Cause 2: Alcohol

Maybe you don’t eat at night, but you do settle down with a relaxing glass of wine to wind down before bed. 

But while alcohol in moderation can induce drowsiness, studies show that it also reduces REM sleep. (10) So even if you don’t wake up during the night after a few drinks, you likely won’t wake up to feel as rested due to poor sleep quality.

Blood Sugar Spike Cause 3: Sleep Deprivation

Lack of sleep can also have detrimental effects on blood glucose levels. Insulin resistance has been implicated in both sleep apnea and experiments involving sleep disruption. Sleep deprivation can cause cortisol to rise, which in turn affects glucose sensitivity.

4. Circadian Rhythm Issues Can Result in Poor Sleep

Your body’s circadian rhythm is the sleep and wake schedule that it naturally follows—your internal clock. Humans as a species have a 24-hour pattern loosely based on light availability.

If your circadian rhythm is thrown off, whether by an underlying health condition, jet lag or simply poor sleep hygiene, your body may not know it’s time to sleep yet.

But if your circadian rhythm is off due to a Circadian Rhythm Sleep Disorder (CRSD), you might be up all hours of the night, be unable to stay asleep, wake up too early or sleep too late. CRSDs are also likely to lead to excessive daytime sleepiness due to poor sleep.

CRSDs occur when there’s a mismatch between your body’s internal clock and the external environment; in other words, you need to get up for work but your body wants 4 more hours of sleep. Lots of things can interfere with your natural rhythm, including:

• Shift work

• Jet lag

• Poor sleep hygiene

• Brain damage from a stroke, dementia, or head injury

• Some drugs and medications

• Older age

• Blindness 

Conclusion

There’s many reasons for poor sleep, but it’s critical to know the root cause behind the symptoms in order to properly treat the issue. 

Once identified, take some steps to reverse those patterns. One test you may want to consider is our DUTCH hormone test, which includes sex hormone health, cortisol levels throughout the the day and more. Learn more here and get tested!

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As you read this article, which sleep blocks did you identify with? Let us know in the comments below!

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Bridgit Danner, LAc, FDNP, is trained in functional health coaching and has worked with thousands of women over her career since 2004. She is the founder of Women’s Wellness Collaborative llc and HormoneDetoxShop.com.

Check out her easy 5-Day DIY Detox Guide here!

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