SLEEP HORMONES
What They Are and How They Affect Your Rest
Sleep is essential for our physical health, mental clarity, and emotional well-being. But have you ever wondered what really controls your sleep-wake cycle?
The answer lies largely in your sleep hormones — the powerful chemical messengers that influence when you feel tired, how well you sleep, and how refreshed you feel the next day.
In this guide, we will explore everything you need to know about sleep hormones, including the major types, how they interact, what disrupts them, and how you can naturally balance them for better rest.
Note: this article does not constitute medical advice. Consult with a health provider before starting any new medical treatment or making lifestyle changes.
Table of Contents
What Are Sleep Hormones?
Sleep hormones are natural substances produced by your body that regulate your circadian rhythm—your internal clock that controls sleep and wake cycles. These hormones respond to light exposure, stress, food intake, physical activity, and other environmental cues to help your body know when it’s time to wind down and when to wake up.
Why Are Sleep Hormones Important?
These hormones are critical for:
Regulating when you feel sleepy or alert
Supporting deep, restorative sleep stages
Influencing mood, energy, and cognitive function
Balancing metabolism and immune function
Preventing long-term sleep disorders
When your sleep hormones are out of sync, your sleep quality, and overall health, can suffer.
The 5 Key Sleep Hormones and Their Functions
There are several hormones involved in sleep regulation, but five stand out as the most influential:
1. Melatonin: The Darkness Hormone
Melatonin is often referred to as the “sleep hormone” because of its direct role in triggering drowsiness.
What it does: Melatonin levels rise in response to darkness and help signal your body that it is time to sleep.
Produced by: Pineal gland in the brain
Peak levels: Usually around 2 to 4 a.m.
Light exposure, especially from screens, can suppress melatonin production and delay sleep onset.
2. Cortisol: The Wake-Up Hormone
Cortisol is often known as the “stress hormone,” but it also plays a role in your sleep-wake cycle.
What it does: Cortisol levels naturally rise in the early morning to help you wake up and feel alert.
Produced by: Adrenal glands
Peak levels: Between 6 and 8 a.m.
When cortisol is too high at night—often due to stress—it can interfere with melatonin and delay sleep.
3. Adenosine: The Sleep Pressure Hormone
Adenosine builds up in your brain the longer you are awake.
What it does: Promotes sleep by increasing the “pressure” to fall asleep over the day.
Produced by: Brain cells as a byproduct of energy use
Cleared during: Deep sleep stages
Caffeine blocks adenosine receptors, which is why it can keep you awake.
4. GABA (Gamma-Aminobutyric Acid): The Calming Hormone
GABA isn’t technically a hormone but a neurotransmitter that plays a major role in sleep.
What it does: Slows brain activity and promotes relaxation, helping you fall and stay asleep.
Produced by: Brain neurons
Target of: Many sleep medications (like benzodiazepines)
Low GABA levels can result in insomnia and anxiety.
5. Serotonin: The Mood and Sleep Regulator
Serotonin is involved in both mood and sleep regulation—and is a precursor to melatonin.
What it does: Helps regulate mood during the day and transforms into melatonin at night.
Produced by: Gut and brain
Linked to: Daytime wakefulness and restful sleep cycles
A serotonin imbalance is often tied to both depression and sleep disturbances.
The Sleep Hormone Cycle: How It All Works Together
Understanding how these sleep hormones interact is key to optimizing your rest.
Morning:
Cortisol spikes to help you feel alert and ready to start your day.
Melatonin levels are at their lowest.
Adenosine starts accumulating gradually.
Afternoon:
Cortisol levels drop, creating a slight dip in alertness (afternoon slump).
Adenosine continues to build, increasing sleep pressure.
Serotonin helps you feel calm but awake.
Evening:
Melatonin begins rising as daylight fades.
Cortisol decreases further.
GABA starts slowing brain activity.
Adenosine is at its highest, making you feel sleepy.
Night:
Melatonin peaks around 2-4 a.m.
GABA and serotonin keep you in deep and REM sleep cycles.
Adenosine is cleared from the brain.
Cortisol begins to rise just before dawn.
What Disrupts Sleep Hormones?
Many modern lifestyle habits can interfere with your sleep hormones, including:
1. Blue Light Exposure
Smartphones, tablets, TVs, and even LED lights emit blue light, which suppresses melatonin production. This can delay sleep onset and reduce sleep quality.
2. Irregular Sleep Schedule
Going to bed and waking up at different times each day confuses your circadian rhythm and throws your sleep hormones out of balance. If you do not have one, use our 7-to-10PM bed time routine for adults to start improving your sleep onset at night.
3. Stress
Chronic stress leads to elevated cortisol levels at night, making it hard to fall asleep and stay asleep. If you feel stress or anxiety, consider a weighted blanket to help settle emotions for sleep.
4. Poor Diet
Heavy meals, processed foods, and caffeine close to bedtime can disrupt adenosine, GABA, and melatonin levels. Follow our guide of what not to eat before bedtime to avoid disrupting sleep hormones and sleep.
5. Lack of Sunlight
Natural light helps regulate serotonin and melatonin levels. Without it, your sleep-wake cycle may be delayed.
6. Alcohol and Drugs
While alcohol may make you feel drowsy initially, it reduces REM sleep and can interfere with GABA and serotonin balance, as well as wake you up to use the bathroom over night.
How to Naturally Boost Your Sleep Hormones
Here are evidence-backed ways to help your sleep hormones work in your favor:
1. Follow a Consistent Sleep Schedule
Go to bed and wake up at the same time each day—even on weekends—to support melatonin and cortisol rhythms.
2. Get Morning Sunlight
Morning light boosts serotonin, which supports daytime alertness and better melatonin production at night.
3. Limit Blue Light at Night
Use blue light filters or glasses and avoid screens at least 1 hour before bed to promote natural melatonin production.
4. Exercise Regularly
Physical activity during the day improves GABA and serotonin levels, promoting deeper and more restful sleep.
5. Eat Foods That Support Sleep Hormones
Foods rich in magnesium, tryptophan, and vitamin B6 help support serotonin and melatonin. Examples include:
Bananas
Nuts and seeds
Salmon
Eggs
Dark chocolate
Oats
6. Create a Calm Bedroom Environment
Your bedding, mattress, and sleep environment play a major role. A cool, dark, and quiet room supports melatonin, GABA, and adenosine function.
Pro Tip: Choosing the right mattress and breathable bedding materials can enhance deep sleep stages where adenosine is cleared and GABA is most active.
Do Sleep Supplements Work?
Several natural supplements aim to support sleep hormones (always consult a healthcare professional before starting any treatment, supplement, or lifestyle change), including:
1. Melatonin Supplements
Can be helpful for short-term sleep issues, jet lag, or shift work, but should be used cautiously and under medical guidance. Read more about melatonin here.
2. Magnesium
Supports GABA production and muscle relaxation.
3. L-Theanine
An amino acid found in green tea that promotes calm and increases GABA activity.
4. Valerian Root
A herbal supplement that may boost GABA for better sleep quality.
5. 5-HTP
A precursor to serotonin, which may help improve mood and sleep, though more research is needed.
Always consult a healthcare provider before starting any supplement regimen, especially if you’re taking medications or have chronic health conditions.
Sleep Hormones and Sleep Disorders
When sleep hormones are disrupted for long periods, it can lead to or worsen several sleep disorders, including:
1. Insomnia
Often linked to low GABA or disrupted cortisol patterns.
2. Delayed Sleep Phase Syndrome
Occurs when melatonin release is delayed, making it hard to fall asleep at a typical bedtime.
3. Sleep Apnea
While primarily a breathing disorder, hormone imbalances may contribute to fragmented sleep and poor recovery. When dealing with sleep apnea, an adjustable bed can make a world of difference!
4. Depression and Anxiety
Disrupted serotonin, cortisol, and GABA can all contribute to mental health issues that affect sleep.
5. Restless Legs Syndrome (RLS)
May be linked to dopamine and GABA dysfunctions, although the exact mechanism is still being studied.
Best Sleep Practices to Support Healthy Sleep Hormones
In addition to lifestyle and diet, the following practices can help balance your sleep hormones naturally:
Stick to a wind-down routine: Start winding down around the same time each evening. Dim lights, avoid stimulation, and incorporate relaxing activities.
Optimize your bedroom setup: Use blackout curtains, a cooling mattress, and cozy bedding that supports temperature regulation.
Stay hydrated—but not too late: Dehydration can affect sleep, but avoid drinking large amounts close to bedtime to prevent nighttime awakenings.
Keep your room cool: Ideal sleeping temperature is between 60–67°F (15–19°C), which supports melatonin production.
Sleep Hormones - Final Thoughts
Your body’s sleep hormones are crucial for maintaining healthy sleep patterns, supporting mental and physical health, and ensuring you feel your best each day. From melatonin and cortisol to GABA, serotonin, and adenosine, each of these chemical messengers plays a unique role in orchestrating your nightly rest.
By understanding what affects these sleep hormones—and how to support them naturally—you can create better sleep habits and improve your overall quality of life. And don’t forget: having the right mattress and bedding can be a powerful ally in optimizing your sleep hormones and deepening your nightly recovery.
References
- National Library of Medicine. (2015). The Impact of Sleep and Circadian Disturbance on Hormones and Metabolism. Retrieved from https://pmc.ncbi.nlm.nih.gov/articles/PMC4377487/
- Sleep Centers of Middle Tennessee. (2022). Which Hormones Affect Sleep? 5 Hormones to Know About. Retrieved from https://sleepcenterinfo.com/blog/which-hormones-affect-sleep/
- National Council on Aging. (2024). Foods That Help You Sleep. Retrieved from https://www.ncoa.org/article/foods-that-help-you-sleep/
FAQ
Most frequent questions and answers
Melatonin is the primary hormone that helps signal your brain it’s time to fall asleep.
Melatonin typically peaks between 2–4 a.m., while cortisol begins rising around dawn to help wake you up.
Yes. Overheating, discomfort, and poor support from your mattress can disrupt deep sleep cycles and interfere with hormone regulation like GABA and adenosine activity.
Yes. Melatonin production tends to decline with age, which may contribute to sleep difficulties in older adults.
The main sleep hormones are melatonin, cortisol, adenosine, and GABA. These chemicals regulate your sleep-wake cycle and help your body know when it’s time to sleep or wake up.
More Sleep Resources
What are the main sleep hormones?
The main sleep hormones are melatonin, cortisol, adenosine, and GABA. These chemicals regulate your sleep-wake cycle and help your body know when it’s time to sleep or wake up.
How does melatonin affect sleep?
Melatonin signals your body that it’s time to sleep. It’s released in response to darkness and helps regulate your internal clock.
Can hormone imbalance cause sleep problems?
Yes, imbalances in sleep hormones like cortisol or melatonin can lead to insomnia, restless sleep, or early waking.
Do natural sleep aids boost sleep hormones?
Some natural sleep aids, like melatonin supplements or magnesium, may help support your body’s sleep hormone production.
When do sleep hormones peak?
Melatonin usually peaks at night, around 2–4 a.m., while cortisol peaks in the early morning to help you wake up.
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Laura Georgieff
Laura is a mother of three who did not sleep through the night for the first 5.5 years of her kids' lives. She is passionate about sleep quality and loves sharing her experience and knowledge of all thing bedding! It is her mission to help you make the best decisions when it comes to sleep and help you get the best deal on the market!
