Microbiome & sleepMicrobiome knowledge

Counting on the microbiome instead of counting sheep

Insomnia has increased with the Covid-19 pandemic: one in 5 people suffered from this sleep-disorder in Germany in 2021. Insomnia has also become a global problem: almost half of all US-Americans say they feel sleepy during the day between three and seven days per week. Here we provide key facts and 3 recommendations for a healthy sleep, based on the latest science.

Why is sleep important?

Sleep of sufficient length and quality is necessary to support both mental and physical health and overall quality of life. Sleep promotes physical recovery & repair, improves heart function, boosts the immune system, and improves your mood.

How does sleep work?

In humans sleep is regulated by a biological “master clock» that follows the natural 24-hour rhythms of light & dark cycles. This clock releases chemicals to the brain called neurotransmitters, including serotonin. Serotonin is present in the body at higher levels during wakefulness and it is estimated that 90% of serotonin is produced in your gut. Another neurochemical, melatonin, peaks during the night. Melatonin is also secreted by the gut and affects the activity of the microbiome. The master clock in the brain is not only controlled by light & darkness, but also responds to other factors including hormones, food intake and the bacteria in your gut, i.e. the gut microbiome. Importantly, scientific studies show that to profit most from the health-restoring benefits of sleep, it is important to follow our natural «master clock» regularly and consistently.

What can I do?

Here are our top three recommendations to adjust your “master clock” for a healthy sleep, based on the latest science of sleep.

  1. Follow regular, healthy routines to give your body the right signals. A regular routine will communicate vital cues to your “master clock” including signalling to your microbiome to establish a natural wake & sleep rhythm. One of the most important things anybody can do to start to lay the foundation for better sleep is probably to stick with a consistent bedtime and wake-up time, even on weekends. As part of this routine, avoid strong light at bed-time and set a curfew for screens: to help you relax, do not use electronics 30 minutes before bed. In general: try to de-stress and mentally wind-down before going to bed.
  2. Eat healthily at regular intervals & nourish your gut-microbiome well. Your gut, known as your second brain, is an important influencer of your “master clock”. A healthy diet rich in unprocessed plant foods, including a rich variety of fresh fruit and vegetables, leads to a more diverse microbiome. A more diverse microbiome can deliver the right neurotransmitters such as serotonin to your brain in a way that fluctuates in natural rhythms. Microbiome-promoted rhythms support a good night’s sleep.
  3. Try supplementing your diet with the right probiotics strains. There are many studies linking a healthy & diverse microbiome to improved sleep and several studies showed improvements of sleep quality with specific probiotic supplementation. Exactly how probiotics may help you improve your sleep is still a subject of investigation, but our knowledge is expanding rapidly. For example, low tryptophan, a precursor of the sleep-modulator serotonin, has been linked to sleep-disturbances. The amounts of tryptophan lower as we age and has been shown to be associated with less sleep. Certain probiotic strains like L. infantis were shown in several clinical studies to improve sleep, probably by increasing natural amounts of tryptophan (and serotonin) in the gut.


To find out which probiotic strains can best support your health interests, press HERE and get your free personalized report today.


Selected scientific literature

Huang et al (2022) Somnologie  26:89–97

Irwin et al (2020) Eur J Clin Nutr 74, 1536–1549 (2020)

Le Morvan de Sequeira et al (2022), Nutrients 2022, 14, 621. 

Li et al (2022), Nature Aging 2, 425–437

Paulose et al (2016) PLoS ONE 11(1): e0146643.

Wagner-Skacel et al (2020), Nutrients, 12, 2198



1 Comment

  1. […] serotonin, in a natural way. Serotonin is also important for a healthy sleep, as described in this sleep blog. In summary, a healthy-gut, a good night’s sleep and a healthy mind are closely […]

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