The Surprising Link Between Hormones and Sleep

The link between cortisol and sleep is strong. Here’s what you should know about this link and how to balance your hormones for optimal sleep health.

What exactly causes poor sleep? Why do some women wake up feeling refreshed while others are always tired? You may be surprised to discover there is a link between hormones and sleep. The link is particularly strong between cortisol and sleep. Here’s what you should know about how hormones impact your circadian rhythm and how lowering your cortisol levels (with help from products like Mixhers Sleep can lead to improved sleep quality.

Our sleep duration and quality are primarily affected by the following hormones: 

• Cortisol
• Melatonin
• Insulin
• Oestrogen
• Testosterone
• Progesterone

Cortisol and melatonin are the hormones we’re going to focus on in this guide. Elevated cortisol levels are notoriously linked to sleep disturbances and adrenal fatigue. Melatonin, on the other hand, is essential for a healthy sleep-wake cycle. 

Melatonin is the body’s main sleep hormone. It rises and falls in response to our circadian rhythm (which is our body’s internal sleep cycle clock). As our body prepares for sleep, it produces more melatonin, which helps us feel relaxed so we can go through the appropriate sleep stages (including slow wave sleep, which is the most restorative type of sleep). When it’s time to wake, melatonin tapers off.

Unfortunately, it’s easy for the circadian rhythm to get out of sync, which can lead to the underproduction of melatonin when it’s time for bed. This, in turn, can lead to sleep disorders such as insomnia and failure to go through all the appropriate sleep stages at night.

Melatonin can be impacted by blue light from phones and other electronic screens. It can also be affected by sleep apnea. Obstructive sleep apnea, in particular, can negatively impact melatonin production in the body. Getting sleep apnea treatment may help return melatonin levels to normal.

Cortisol can also affect melatonin. When cortisol levels rise, melatonin levels drop (and vice versa). We’ll talk about what causes elevated cortisol in a minute.

Cortisol and sleep are more closely connected than many of us realize. Cortisol is also known as the stress hormone because it goes hand-in-hand with excess stress. Cortisol is produced by the adrenal gland. To be more specific, it’s produced by the hypothalamic pituitary adrenal axis (also known as the HPA axis). This axis and our cortisol rhythm can have a profound impact on our sleep cycles.

Let’s talk about the role of cortisol in sleep. When our cortisol levels are too high, they can wreak havoc on our circadian rhythm and cause sleep problems. When cortisol levels are in a normal range and we don’t have problems with sleep deprivation, we’re more likely to experience normal sleep physiology, which looks like this:

Stage 1: Light Sleep

During stage 1 sleep (which is a light level of sleep that lasts about 5-10 minutes), we go through the transition between wakefulness and sleep onset. This stage of sleep is characterized by very slow brain waves called mixed frequency theta waves.

Stage 2: Light Sleep

Stage 2 is also considered a light sleep stage. It lasts around 20 minutes in most people and involves rapid bursts of brain wave activity interspersed with mixed-frequency brain waves. Body temperature begins to drop during stage 2 sleep and the heart rate slows down.

Stage 3: Deep Sleep

The third stage of sleep is characterized by anywhere between 20% and 50% delta waves (which are slow brain waves). This is the time when our body transitions from light sleep to very deep sleep.

Stage 4: Deep Sleep (Delta Sleep)

We experience more than 50% delta brain waves in stage 4 sleep. Sometimes stage 4 sleep is also referred to as delta sleep because of the brain waves we experience at this time. Most people with healthy sleep patterns remain in delta sleep for around 30 minutes.

Stage 5: REM Sleep

Rapid eye movement sleep (also known as REM sleep) is the fifth stage of sleep we go through at night. During this stage, our respiration and brain activity increase. This is the stage when dreaming occurs. During REM sleep, we experience a combination of theta waves and mixed frequency EEGs. In adults with healthy sleep cycles, REM sleep occurs approximately once every 90 minutes.

The body goes through these different sleep stages throughout the night. They don’t always occur in order. For example, all sleep begins in stage 1 and progresses through the other stages until stage 4. After that, the body goes through stages 3 and 2 again before jumping to stage 5. After stage 5, the body usually returns to stage 2.

If you’re wondering where cortisol fits into this process, here’s what you should know about how cortisol affects sleep. Approximately two or three hours after the onset of sleep, cortisol begins to rise. It usually peaks around 9:00 a.m., and then levels begin to gradually decline throughout the day.

A healthy cortisol rhythm can help us feel awake in the morning, but a cortisol concentration that’s too high can disrupt the normal sleep stages when levels rise too much or at inappropriate times. That’s why it’s important to learn how to keep cortisol levels low in the body—especially as we approach bedtime.

We know that elevated cortisol can cause sleep loss. But it can also cause more serious sleep disorders such as insomnia. When the body’s normal cortisol rhythm becomes disrupted, it can lead to total or partial sleep deprivation.

In addition to insomnia, too much cortisol can also lead to fragmented sleep and shortened overall sleep time. If you’re stressed and you wake frequently at night, you’re probably experiencing cortisol awakening.

To keep these things from happening, we need to understand as much as possible about cortisol and sleep, as well as how to lower cortisol levels before we experience out-of-control cortisol secretion. But before we can lower cortisol levels, we need to know what causes them to be high in the first place.

The primary culprit behind high cortisol is stress (which shouldn’t come as a surprise, since cortisol is also known as the stress hormone). Chronic stress impacts so many of us these days, but too often we underestimate the influence it can have on our physical and mental health.

People who experience high stress levels almost always have correspondingly high cortisol levels. The relationship between sleep and stress is still being studied, but it’s clear that stress can lead to partial or total sleep deprivation. In addition to stress, other causes of high cortisol levels include diet, certain autoimmune diseases, and trauma.

There are a few things you can do to lower the stress hormone causing your sleep loss. Here’s how to remove cortisol from your body:

• Exercise regularly
• Take fish oil and supplements with ashwagandha and other anti-inflammatory herbs
• Try meditation and deep breathing techniques
• Take a salivary cortisol test to see how high your cortisol is
• Take supplements such as Mixhers Sleep if you need help lowering cortisol naturally
• Try sleep training or integrative therapeutics to help you avoid further sleep loss
• Get treatment for high blood pressure

Balancing your hormones can help you achieve better sleep and avoid unwanted sleep restrictions. Mixhers Sleep contains the hormone melatonin, which can help you fall asleep faster and achieve higher-quality sleep. For more advice about using natural sleep medicine and supplements to help you get good sleep, visit Mixhers Resources.