Skip to main content

How Gut Health and Sleep Affect Each Other

There is ample evidence that the gut microbiome influences not only digestion and metabolism but also sleep and mental state. This occurs via the gut-brain axis, in close interaction with physiological stress, emotions, and circadian rhythms.

Sleep patterns are influenced by changes in intestinal permeability (intestinal permeability), activation of the immune system, inflammation, energy production, and diversity of intestinal bacteria (bacterial diversity).

An altered microbiome has been observed in patients with chronic fatigue syndrome. This suggests that an unbalanced gut could promote sleep problems.

You may have read about the importance of your gut health for a healthy brain. More and more studies are observing a link between gut flora and stress, anxiety disorders, and depression. Your gut bacteria may even influence how well you sleep.

Sleep is necessary for recovery from physical and mental stress and memory function, among other things.

A recent meta-analysis identified insomnia as an important predictor of depression, anxiety, alcohol abuse, and psychosis. This highlights the critical importance of sleep for psychological well-being.

gut health and sleep

Gut And Brain Connection

The intestine is densely populated by microorganisms such as intestinal bacteria, viruses, and fungi. For the most part, gut bacteria and the gut live in harmony. When we are healthy, the bacteria are kept safely inside the gut. So how can the bacteria communicate with the outside?

The gut has a direct relationship with the central nervous system (CNS) called the “gut-brain axis.” This allows the gut to send signals to the brain and receive signals from the brain. Gut bacteria play a key role in this communication.

In one study, administration of the bacterial strain Lactobacillus (a bacterium also found in yogurt) reduced anxiety levels in mice. However, this doesn’t work if you cut the vagus nerve – the main connection between the brain and the gut. That’s because bacteria communicate with the brain via the vagus nerve. When intestinal bacteria digest fiber, they produce metabolites that affect levels of serotonin, cortisol, and tryptophan, for example. These, in turn, can activate the vagus nerve.

There are many other ways that gut bacteria can affect the brain, including bacterial metabolites and toxins, absorption of nutrients, alteration of taste receptors, and stimulation of the immune system. For example, D-lactic acid and ammonia produced by gut flora can enter the central nervous system via the vagus nerve, affecting brain function, stress responses, and sleep.

Why Does Poor Sleep Affect Our Digestion?

Because of the connection between the gut and the brain (gut-brain axis). This is also reflected in the dynamic interaction between digestion and sleep. Studies show that digestive disorders such as gastritis (inflammation of the gastric mucosa), constipation, or gastroesophageal reflux disease can lead to sleep problems.

On the other hand, it has also been shown that sleep disturbances or poor sleep can have a negative effect on our digestion.

This can result in constipation as well as diarrhea and an unpleasant feeling of pressure in the abdomen. And also the composition of gut bacteria changes, disrupting the sleep-wake cycle.

This can cause stress reactions, which in turn can weaken the intestinal barrier and immune system.

Scientific studies show that if you are repeatedly exposed to a lot of stress, inflammation can spread to the surface cells of the gut, so many people respond to stress and sleep deprivation with diarrhea.

Stress Reduces Gut Barrier Function

Chronic overload, fuss, and pressure affect our intestinal nervous system and gut bacteria in different ways.

A healthy gut forms a tight barrier between the gut contents and the rest of the body tissue. These so-called tight junctions seal the gut from the outside so that bacteria and harmful products of metabolism cannot enter the body and the bloodstream. Stress can weaken this intestinal barrier. Stress hormones attack and break down tight connections. As a result, a leaky gut (leaky gut syndrome) can develop. This, in turn, is suspected of causing other diseases such as diabetes, obesity, liver obesity, and depression. Especially chronic stress, to which you are exposed for too long and which lacks an important balance, weakens the important intestinal barrier. Short periods of stress are part of life.

We must learn to deal with them – and take timely countermeasures if they become too much! To a certain extent, our body and a balanced gut can alleviate stress and restore the leaky gut barrier. The foundation for this is a healthy lifestyle – a balanced diet, exercise, a good work-life balance, and relaxation techniques.

Does Irregular Sleep Really Influence Our Microbiota?

The circadian rhythm is important not only for determining sleep and eating patterns but also for the activity of all hormonal axes, cell regeneration, and brain activity, among other functions.

The intestinal flora, intimately related to these processes, secretes different molecules at certain times of the day. Thus, at night, those related to energy metabolism, cell repair, and cell growth predominate.

During the day, gut bacteria will produce molecules that consolidate their own colonization of the gut. Thus, overnight fasting is beneficial for the production of short-chain fatty acids, such as butyrate. This protects the intestine in addition to regulating glucose levels through various glucose-related hormones. Or propionate, which regulates fat metabolism in the liver.

On the other hand, metabolites excreted during feeding times are linked to the absorption of proteins, lipids, and amino acid metabolism.

For example, an imbalance in the microbiota can lead to a reduction in the availability of tryptophan for serotonin synthesis at the brain level. In addition, some studies have found that it is linked to the production of melatonin (the sleep hormone).

Less sleep causes the diversity and quantity of intestinal bacteria to be altered. This results in metabolism problems that could seriously affect people who do not have a correct bedtime schedule.

How Sleep Deprivation Affects?

Sleep-deprived people have changes in their microbiota similar to those seen in obese people compared to healthy people. They show 20% less sensitive to insulin, which increases the likelihood of developing type 2 diabetes.

poor gut health and sleep

It should also be kept in mind that late bedtime acquires undesirable habits, such as eating late at night, which can disrupt sleep and create a circadian and non-circadian cycle.

Abusing alcohol and fast food at bedtime disrupts the rhythm of the gut microbiota. This leads to dysbacteriosis.

This is a change in the composition and/or function of the bacteria that coexist in our body as commensals, and it can lead to gut inflammation and an increased risk of other diseases.

Microbiota and Sleep Disorders

Poor quality sleep influences the important work of hunger and satiety hormones that regulate our food intake.

The connection between sleep and appetite is extremely important since lack of sleep can unbalance our appetite, increase our food cravings and lead to weight gain. This is because lack of sleep decreases the level of a hormone called leptin, which is responsible for our feeling of satiety.

It also increases the level of ghrelin, a hormone responsible for hunger. So when we lack sleep, leptin cannot control or signal when we are full; instead, ghrelin tells us to keep eating even more. This helps explain why sleep-deprived people tend to gain weight faster and have a higher risk of obesity.

Lack of sleep also impacts the parts of our brain responsible for impulse control. As a result, many sleep-deprived people report that they are unable to control themselves when it comes to overeating. All of this has consequences for the well-being of our gut and its ecosystem.

General Sleep Recommendations

Sleep is extremely important and also helps prevent two diseases that are among the leading causes of death in many countries:

  • Heart disease
  • Cancer

How Much Sleep Do We Actually Need?

Age GroupRequired Sleep for Optimal Health
Newborns (0 to 3 months)14 to 17 hours
Infants (4 to 11 months)12 to 15 hours
Toddlers (1 to 2 years)
11 to 14 hours
Kindergarten children (3 to 5 years)10 to 13 hours
School children (6 to 13 years)
9 to 11 hours
Teenagers (14 to 17 years)8 to 10 hours
Adults (18 to 64 years)7 to 9 hours
Seniors (65 years and older)7 to 8 hours

Nourish the Intestinal Flora

Achieving and nourishing a healthy gut flora isn’t as hard as you might think. It’s likely that this adjustment will improve more than just your sleep. However, you need to proactively take the initiative to adjust your lifestyle. This includes:


  • Eat plenty of fermented foods – healthy choices include lassi, fermented kefir made from pasture-raised milk, natto (fermented soy), and fermented vegetables.
  • Take probiotic supplements – probiotics and prebiotics make sense to target your gut flora and build your immune system.
  • Increase your intake of soluble and insoluble fiber and focus on fresh vegetables, nuts, and seeds, including sprouted seeds.
  • Get your hands dirty in the garden – Exposure to bacteria and viruses can help strengthen your immune system and build long-lasting immunity to disease. Work in the garden and get your hands dirty. This will reacquaint your immune system with beneficial microorganisms on plants and in the soil.
  • Ventilate – Since the beginning of time, humans have spent much of the day outdoors. Nowadays, we spend most of our time indoors. This has its advantages, of course, but it also changes the composition of the bacteria that live in our bodies. Scientific research shows that airing out can improve natural airflow and the diversity and health of microbes in the home, which in turn benefits your health.
  • Wash your dishes by hand instead of in the dishwasher – Research has shown that washing dishes by hand leaves more bacteria on dishes than dishwashers. Eating from these less sterile plates can reduce your risk of allergies by stimulating your immune system.

You should avoid:

  • Antibiotics unless used are absolutely necessary. If you do use antibiotics, be sure to populate your gut with fermented foods and/or a high-quality probiotic supplement with good bacteria
  • Meat from conventional livestock and other animal products – Animals from conventional factory farms are routinely given low doses of antibiotics along with their feed, which is most often genetically modified grains with copious amounts of glyphosate. These substances are widely known to kill bacteria on a large scale
  • Chlorinated and/or fluoridated water – especially when bathing or showering, which is even worse than drinking such water
  • Processed foods – Excess sugar is a food source for harmful bacteria. Food emulsifiers such as polysorbate 80, lecithin, carrageenan, polyglycerols, and xanthan gum also appear to have a negative effect on gut flora.
  • Agricultural agrochemicals: glyphosate (Roundup) in particular is a known antibiotic and has the potential to kill many beneficial gut bacteria if you eat food contaminated with it
  • Antibacterial soap – This kills both good and bad bacteria, contributing to the development of antibiotic resistance

Feeling sluggish or unproductive lately? Then it’s time to improve your sleep habits. Good sleep is an essential factor in improving mood and overall health. However, many people do not ensure an adequate and good sleep, increasing their risk of various ailments.


Our sleep and digestion are essential for good health. Both are directly related to each other. If we have a good and diverse intestinal flora, we sleep better. If we sleep well, this has a positive effect on our intestinal flora. All this fits into our rhythm and our internal clocks can work properly and on time. With this smooth interaction, you reduce the risk of serious diseases and do something good for your overall health. So make sure to support your digestion and get back to a good night’s sleep.

How Gut Health Impacts Sleep? - Video

Sleep Disturbance and Intestines - FAQ

❓ Can Your Gut Health Affect Your Sleep?

With most serotonin produced in the gut, poor gut health can easily cause sleep diseases, such as insomnia and chronic fatigue.

❓ Do Probiotics Help You Sleep Better?

Yes. Research now suggests that probiotics have a direct effect on sleep quality, helping you to fall asleep more easily at night and encouraging healthy sleep cycles.

❓ Do Gut Bacteria Produce Melatonin?

Melatonin is produced in the gut as well as the brain, and evidence suggests that intestinal melatonin may operate on a different cyclical rhythm than the pineal melatonin generated in the brain.

Jessica Clavits

Jessica Clavits

Hi! I'm Jessica! I keep this blog about personal care.