Waking up throughout the night can really take a toll on your body and mind. You feel exhausted when you go to bed, and yet you still can’t manage to get a full nights’ sleep. What’s going on?
There can be many different reasons for restless sleep. Diet plays a big part, especially if you’re drinking too much caffeine (or alcohol) late in the day or evening. Sleep hygiene is also a contributor: if your bed is uncomfortable, or if there’s light and noise in your room during the night, you’re more likely to toss and turn.
All of these things can lead to the main reason you can’t stay asleep: cortisol.
How adrenals and cortisol affect sleep
As explained in my previous blog, cortisol is a stress hormone. It’s produced by the hypothalamic-pituitary-adrenal (HPA) axis, which comprises your hypothalamus, pituitary gland, and adrenal glands.
To make cortisol, your hypothalamus releases a substance called corticotropin-releasing hormone (CRH), which stimulates your pituitary gland to release another hormone, adrenocorticotropic hormone (ACTH). ACTH then triggers your adrenal glands to produce cortisol. When there’s enough cortisol in your bloodstream, the hypothalamus stops releasing CRH. That’s why the HPA axis is often referred to as a feedback loop.
The HPA axis also helps to coordinate your sleep-wake cycles. However, hormones such as melatonin and cortisol have a major impact on this cycle, which in turn affects the HPA axis.
Melatonin is the ‘sleep hormone’. It’s produced by the pineal gland in the brain and then released into the bloodstream according to a circadian rhythm, which means it’s designed to be in sync with daytime and nighttime. This is an evolutionary trait from when humans’ sleeping schedule was regulated by natural light. When the light dims in the evening, melatonin is released; when light increases in the morning, your melatonin is suppressed. In our ancestors’ time, this trait meant they would go to sleep at night and wake in the morning.
Just as morning light reduces melatonin, it also signals for your brain to release cortisol. Cortisol acts like your “wake up” hormone, and it’s supposed to peak in the morning and fall at night, so that you are only ‘awake’ and alert during the day.
In short: melatonin and cortisol work in opposition to one another. When melatonin is high, cortisol should be low, and vice versa.
Why we aren’t sleeping well anymore
Modern life has completely upset our normal sleep-wake pattern, which in turn has affected the release of melatonin and cortisol. It’s quite common for us to get up when our alarm goes off while it’s still dark. We then spend all day indoors and go home in the dark. We then stay up throughout the evening using artificial light and looking at backlit devices.
It’s hardly surprising that all this “modern circadian rhythm” has confused our body’s natural signals. Our brains don’t know when to release melatonin at night, which means we are no longer in sync with the waking effect of the sun and the sleep-inducing darkness of night. And this affects our sleep.
Studies show that melatonin can be partially suppressed by exposure to light, so those LED screens can actually prevent it from being released. When this happens, your brain continues to release cortisol instead, which increases your alertness and arousal. This in turn upsets your REM sleep patterns when you actually fall asleep. It’s the ultimate recipe for broken sleep.
The longer the HPA axis remains active, the more disrupted your sleep cycles become. Sleep deprivation throws your HPA axis even further out of balance, which makes it more difficult to get back to a normal sleep-wake pattern.
Worse still, sleep deprivation affects your body’s ability to store and control energy availability. If your sleep is restricted for just five days, your insulin response can be 40% slower than normal.
How to regulate your sleep-wake pattern
Your body’s circadian production of cortisol is affected by many different factors – but many of these can be managed.
Diet: a high intake of refined sugars, salt, and trans fats can cause you to wake up more often during the night. Studies show that a diet low in fibre and high in sugar and saturated fat leads to lighter, less restorative sleep with more arousals.
Stress and trauma: Chronic or ongoing stress can cause your HPA axis to continue producing cortisol. Elevated blood levels of cortisol mean that your body stays in the high-alert mode, otherwise known as “fight or flight”. This is bad news for your ability to sleep and relax.
Artificial light: As mentioned above, your brain responds to light – both natural and artificial. Constant exposure to indoor lights and LED screens can interfere with your body’s interpretation of day or night.
Fluctuating bedtimes: Many of us have a wildly erratic bedtime schedule that swings all over the place between weekdays and weekends. This prevents our brain from establishing a steady sleep pattern.
Age: Melatonin production decreases as you get older. From the age of 40, your body produces around 60% of the amount of melatonin as it did in your younger years. Unfortunately, this one can’t be altered!
Naturopathic approach to restoring restful sleep
You may have heard people say, “Oh, I don’t need sleep!” But the truth is that restful sleep is essential for whole-body health. Your mind, body, and spirit depend on it.
As a naturopath, I help you identify and address the factors that might be causing you to wake up throughout the night. In many cases, this is down to stress, anxiety, diet, and emotional imbalances.
Once we’ve figured out what’s keeping you awake, we’ll talk about how to bring your mind and body back into balance. This might involve behavioural techniques that help to switch off your “fight or flight” mode, like breathing exercises, physical activity, or meditation.
There are also many powerful natural medicines that can help to reduce the stress response and promote healthy sleep.
If you’re tired of being tired, get in touch with me here. It’s time to rest up!