Insomnia and Gut Health: How Your Microbiome Controls Your Sleep

They say you should always trust your gut feeling—and in this case, your gut is quite literally telling you something important! Beyond digestion, your gut plays a key role in various factors that impact your life, such as your mood, energy levels, immune system, and even how well you sleep. 

It is like your body’s hidden control centre, constantly working to keep you balanced and healthy. When any of these functions are disrupted, it can throw off your well-being, affecting not just your physical health but also your mental clarity, emotional stability, and overall growth. Understanding the importance of your gut can be a game-changer for your health. 

By taking care of your gut, you essentially support your body’s ability to function at its best, which leads to long-term health and vitality.

The Gut-Brain-Sleep Connection

Your gut and brain are constantly communicating through the gut-brain axis—a powerful two-way connection where gut bacteria influence neurotransmitters, hormones, and inflammation, all of which play a crucial role in your sleep quality.

At the core of this relationship is your microbiome—a vast ecosystem of trillions of bacteria, fungi, and other microbes that regulate everything from digestion to mental well-being. When your gut microbiome is out of balance, it can disrupt your sleep cycle, leaving you feeling restless yet exhausted.

What makes this even more challenging is the vicious cycle it creates—poor gut health can lead to sleep disturbances, and in turn, lack of sleep further weakens your gut, making it harder for your body to restore balance.

How Your Microbiome Affects Sleep

1. Serotonin and Melatonin Production

You might associate serotonin with mood regulation, but what most people are unaware of is the fact that nearly 90% of your body’s serotonin is produced in the gut. Since serotonin is essential for melatonin production, which is the hormone that regulates your sleep-wake cycle, an imbalanced gut can lead to irregular sleep patterns. When your gut lacks diverse and beneficial bacteria, serotonin levels may drop, disrupting melatonin production and making it harder to fall or stay asleep.

2. Inflammation and Sleep Disruptions

An unhealthy gut, regardless of the reason, can trigger chronic inflammation. This does not just affect digestion; it also overstimulates your nervous system, which keeps you in a state of alertness when you should be winding down. Conditions like Leaky Gut Syndrome (where the gut lining becomes more permeable, allowing harmful substances into the bloodstream) have been linked to fragmented sleep, difficulty staying asleep, and overall lower sleep quality.

3. Blood Sugar and Midnight Wake-Ups

Your gut microbiome plays a key role in regulating blood sugar levels. When it is out of balance, sudden drops in blood sugar can trigger a spike in cortisol, which is the stress hormone. This causes you to wake up in the middle of the night. Diets high in processed foods and sugar can further disrupt gut bacteria, leading to unpredictable blood sugar crashes that interfere with restful sleep.

4. Circadian Rhythm and Gut Health

Just like you, even your gut bacteria follow their circadian rhythm. Disruptions to your internal clock—such as late-night eating, inconsistent sleep schedules, or excessive blue light exposure—can throw off this rhythm, affecting digestion and sleep quality. 

An out-of-sync microbiome can result in:

• Trouble falling asleep
• Less deep, restorative sleep
• Increased night-time awakenings

Keeping your gut healthy means supporting your body’s natural sleep cycle, helping you rest better and wake up feeling refreshed.

How to Improve Your Gut for Better Sleep?

The good news is that your microbiome is highly adaptable. By making intentional lifestyle changes, you can support a healthier gut and, in turn, enjoy deeper and more restorative sleep.

Fuel Your Gut with Prebiotics and Probiotics

Prebiotics: These act as food for beneficial bacteria. Include fibre-rich options like garlic, onions, leeks, bananas, and asparagus in your diet.

Probiotics: These introduce good bacteria into your gut. Fermented foods like kefir, kimchi, sauerkraut, and natural yoghurt can help maintain a healthy balance.

Prioritise Fibre-Rich Foods

A diet low in fibre can lead to gut imbalances that disrupt sleep. Whole grains, legumes, and a variety of colourful vegetables help nourish your microbiome as they support better digestion and sleep quality.

Limit Ultra-Processed Foods

Refined sugars, artificial sweeteners, and processed foods can feed harmful bacteria, causing inflammation and blood sugar fluctuations that negatively impact both gut health and sleep. Cutting down on these can help restore balance.

Maintain a Consistent Eating Schedule

Eating at regular times each day supports a stable microbiome, while late-night snacking can throw off this rhythm and lead to restless sleep.

Manage Stress

Chronic stress disrupts gut health by increasing cortisol levels, which in turn suppresses sleep hormones. Incorporate stress-relief techniques like meditation, deep breathing, or gentle movement to create a healthier gut-sleep connection.

Stay Active

Regular movement promotes a thriving gut microbiome and helps regulate circadian rhythms. Even a simple 30-minute walk each day can positively impact digestion, reduce inflammation, and improve sleep quality.

What Have We Learnt? 

If sleep has been hard to come by despite your best efforts, your gut health might be the missing piece of the puzzle. Rather than relying solely on quick fixes like melatonin supplements, take a closer look at how you nourish your body. Small, mindful changes in your diet and lifestyle can create a ripple effect, leading to deeper, more restorative sleep.

After all, good sleep isn’t just about what happens at night; it is more about what is built by the choices you make throughout the day.