Why can't I sleep? Three causes to look at first
"Why can't I sleep?" is a question I hear all the time, often from people who have already tried magnesium, lavender and a new pillow. In this article I take you through three separate roots of poor sleep: the stress response and the nervous system, cortisol rhythm and blood sugar, and hormones. You will see what each pattern looks like, how it works in the body and where to start looking for your own.
How sleep is meant to work
Two things set up a night's sleep. The first is sleep pressure. The longer you stay awake, the more adenosine, a chemical by-product of brain activity, builds up, and the sleepier you become. Caffeine blocks adenosine's action, which is one reason an afternoon coffee can delay sleep that evening. The second is your body clock, a small cluster of cells in the brain that follows the daily cycle of light and dark and tells the rest of the body what time it is.
As evening arrives, the body clock releases melatonin, core body temperature drifts down and cortisol, the main stress hormone, falls towards its lowest point of the day. At the same time, a calming brain messenger called GABA slows the nerve cells that keep you alert. Sleep comes when these signals line up: enough sleep pressure, a dark evening, low cortisol and a quiet nervous system.
Once asleep, you move through cycles of light sleep, deep sleep and dream sleep (REM) roughly every 90 minutes. Deep sleep is concentrated in the first half of the night and dream sleep becomes longer towards morning, which is why sleep that breaks up in the second half of the night can leave you feeling short-changed even when you were in bed for eight hours.
Each of the three causes in this post interferes with a different part of that sequence. The stress response keeps the nervous system alert when it should be winding down. A disrupted cortisol rhythm interferes with the timing signals. Changing hormones affect GABA, the brake pedal on nerve activity.
Why can't I sleep when I have tried everything?
Magnesium, lavender, passionflower and valerian are all popular sleep aids, and each one suits some people well. Trouble starts when a remedy chosen for one pattern is used on another. Sleep sits downstream of several body systems, so a remedy aimed at one of them may make little difference when the problem lies in another.
I work in a particular order. The first thing I establish is whether the problem is long-term or came on suddenly, because a problem that has run for years and one that started last month call for different questions. The second is the shape of the night: whether it is hard to fall asleep, or whether sleep comes easily and then breaks in the small hours. Those two questions narrow the search before any herb or supplement enters the picture.
If you would like a wider tour of the options first, my post on natural sleep aids explained goes through them one at a time.
The stress response and the nervous system
Picture the evening. By four, five or six o'clock you are exhausted. Your body is tired and your brain feels finished. You get into bed, and it is as if a light goes on: your mind starts replaying the day's conversations, working through tomorrow and chattering on, however hard you try to quieten it.
Many people in this pattern find that magnesium and sleep meditations make little difference. One explanation sits upstream of bedtime. Your stress response runs on a chain of signals: the hypothalamus signals the pituitary gland, which signals the adrenal glands to release cortisol and adrenaline. Those hormones raise your heart rate and alertness, and they hold off sleep. After a short-lived stress the chain switches off. After months or years of pressure it keeps firing, and the body takes a long time to read the evening as safe.
How long this has been running shapes where to begin. A few weeks of pressure is a different starting point from several years of it, and the source matters as well: family strain, a difficult relationship, work and grief each need attention in their own right. Herbs and supplements can sit alongside that work.
Nervines are herbs traditionally used to support the nervous system, and a calming one can take the edge off an evening. Lasting change usually comes from identifying what keeps the stress response switched on. I explain how nervines work in what nervine herbs are and how they support the nervous system.
The other half of the picture is the parasympathetic nervous system, the body's rest-and-digest branch. It takes over when the brain judges that the threat has passed, and its signals slow the heart, deepen the breath and let digestion resume. A stress response that has been running for a long time can leave that handover slow.
Some evening habits give the nervous system a clear signal that the day has finished. Dimming lights and screens for the last hour, writing tomorrow's task list before you leave the kitchen, and a few minutes of slow breathing with a longer out-breath than in-breath are three that many people find worth trying. I go into the specifics in the next video in this series.
Cortisol rhythm and blood sugar
Cortisol is a hormone we need. It gets us moving in the morning and keeps us alert and motivated through the day. The question is timing.
Cortisol follows a daily rhythm. It rises in the early hours before waking, peaks shortly after you get up, then falls through the day towards its lowest point in the late evening. That fall lets the body move towards sleep. Around dawn it begins to rise again, which is part of how the body prepares you to wake. When the rhythm is disrupted, cortisol can sit at the wrong level at the wrong time.
Blood sugar has its own daily rhythm and interacts with this one. When blood glucose dips, cortisol and adrenaline are among the hormones that bring it back up, and both raise alertness as they do so. Long-running stress, irregular meals and alcohol in the evening can each change how steady blood sugar stays through the night. Alcohol deserves a special mention: it can help some people fall asleep, and it tends to fragment sleep later in the night.
Light is the strongest cue your body clock has. Daylight in the first hour after waking, ideally outdoors, tells the clock that the day has begun and helps anchor the cortisol rise to the right time. A consistent wake time works in the same direction. Many people find that a regular start to the day changes the evening more than anything they do at bedtime.
The pattern people describe here differs from the one above. They fall asleep without trouble, then wake in the early hours, often wide awake, and cannot get back to sleep. Waking in the small hours is common, and there is rarely one reason: stress, blood sugar, hormones, alcohol and sleep habits can all play a part. In my practice, falling asleep easily and then waking wide awake is a pattern that often travels with cortisol and blood sugar.
The two patterns can appear together, and the nervous system often needs attention alongside the cortisol picture. Each one still deserves its own approach. For more on how a long-running stress response reaches into hormones, digestion and mood, see how chronic stress affects your body. Steadying cortisol rhythm and blood sugar, and the practical steps that go with them, get their own video in this series.
Hormones and sleep
The third area is most common in perimenopause and menopause, and it can affect other people too. A frequent reaction is "but I am not having hot flushes." Hot flushes are one sign of hormonal change, and sleep can be affected years before any appear.
Progesterone and oestrogen change gradually across perimenopause, rising and falling unevenly for years before settling at new levels. Progesterone matters here because of GABA. GABA is a neurotransmitter, a chemical messenger, that slows activity in the brain and helps switch the mind off at night. Progesterone and its breakdown product allopregnanolone act on GABA receptors, which is one reason progesterone has a calming influence. When progesterone falls or swings, that calming influence weakens, and sleep can become lighter and harder to enter.
Oestrogen also influences serotonin, which the body uses to make melatonin. As oestrogen fluctuates, that pathway fluctuates with it, which is one reason sleep often changes in the years before periods stop. This can look like the first pattern, a busy mind at bedtime, with a different driver, so the approach differs.
The menstrual cycle gives a smaller version of the same picture. Progesterone falls in the days before a period, and many women notice lighter or more fragmented sleep at that point in the month. Night sweats can also wake people directly, and they tend to become more frequent as periods change. If your sleep varies across your cycle, or changed around midlife, hormonal influence is worth including in your thinking.
Two areas I will cover in the video on hormone-related sleep are looking after liver function, which is involved in clearing used hormones, and eating foods that contain phytoestrogens, such as flaxseed and legumes. If you would like the background first, how the female hormonal cycle works explains the monthly rhythm these changes build on.
Which pattern comes first for you?
Most people recognise themselves in more than one pattern. A useful way to start is to notice which one arrives first. This is a way to organise what you notice, and a practitioner can help you assess the rest.
The stress response. Exhausted by early evening, then a mind that switches on in bed and will not quieten. Falling asleep is the difficult part.
Cortisol rhythm and blood sugar. Falling asleep is easy, and waking in the early hours wide awake is the difficult part.
Hormones. Sleep that changed as your cycle or midlife did, sometimes with a busy mind and sometimes with no obvious trigger at all.
When to see your GP
Some sleep problems need a medical assessment. See your GP if you snore loudly, wake gasping, feel very sleepy in the daytime, or if your sleep has been poor for a long time and is getting worse.
If you take prescribed sleeping tablets, sedatives or antidepressants, keep taking them as prescribed and talk to your GP before changing anything. My post on how naturopathic remedies can work alongside conventional medicine covers how to approach this.
Herbal support for the night while you work out the pattern
Herbs that calm the nervous system belong to a group called nervines, and Western herbal medicine has used them for a long time. Several of them, valerian and hops among them, are also traditionally used for sleep. Many people want to begin supporting their sleep while they work through the detail of their own pattern, and this is where I start.
I formulated Sleep Deep at EarthWise as a starting point for the night itself. It combines six herbs with three Australian Bush Flower Essences.
Passionflower (Passiflora incarnata). A nervine traditionally used to support relaxation and a settled evening. It has a long history in Western herbal practice.
Valerian (Valeriana officinalis). One of the best-known traditional herbs for sleep, used to support relaxation and healthy sleep patterns. Its use in Europe goes back centuries.
Lemon balm (Melissa officinalis). Traditionally used to support relaxation and a calm mind. Herbalists have used it for centuries.
Lime flower (Tilia × europaea). Traditionally used in European herbal practice to support relaxation, often as an evening tea.
Hops (Humulus lupulus). A bitter herb, best known in brewing, that has a traditional place in herbal practice for supporting sleep.
Lavender (Lavandula angustifolia). Traditionally used to support relaxation, and valued in herbal practice for its aroma as well as its taste.
Australian Bush Flower Essences (Black Eyed Susan, Boronia and Crowea). Flower essences belong to a separate tradition from herbal tinctures. They are prepared from flowers infused in water and are used in that tradition for mental and emotional states.
Sleep Deep is designed to support the night. My intention with it is that it forms the first part of a protocol, used while you find out which system needs the most attention. The three sleep duos pair it with a daytime tonic for each system: Unwind & Sleep with Calm Nerve for the nervous system, Restore & Sleep with Adrenal Guard for energy and blood sugar, and Balance & Sleep with Hormone Harmony for hormones. The daytime tonic supports that system through the day, and Sleep Deep supports the night. Both sit alongside the daytime steps above.
Where herbal support fits
Herbal support suits the first stage, while you work out the pattern. Caffeine timing, morning light, alcohol and the load on your stress response all still shape the night, and a herb sits alongside each of them. Snoring, gasping and heavy daytime sleepiness are matters for your GP, as above. Sleep Deep is best seen as one part of the picture, together with the changes in this post and, later, the steps from the video on whichever pattern fits you. Full safety information sits on each product page.
What comes next in this series
Each of the three causes gets its own video: the stress response, cortisol rhythm and blood sugar, and hormones, each with practical steps. Subscribe to the EarthWise Natural Health YouTube channel to see them as they are published. If you would like a starting point today, the EarthWise health quiz is a good place to begin.
Three systems can each sit behind a sleep problem, and they often overlap. The most useful early step is to work out which one comes first for you and start there, with your GP as the first call if anything in the GP section above applies.
Sarah Burt is a registered naturopath, medical herbalist and iridologist with 25 years of clinical experience. All EarthWise tonics are formulated by Sarah based on her clinical protocols.
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This article is for informational purposes only and is not intended to diagnose, treat or cure any health condition. Always consult a qualified health practitioner before making changes to your health regimen.
