What impact does our gut microbiome have on sleep?

It’s only recently that we’ve begun to understand the significance of gut health for our overall health and wellbeing.

The gut was once considered a fairly unimportant organ, but recent research has led scientists to believe that gut health actually affects the entire body –  from the brain and mental health, to digestion and our tendency to gain weight, immunity and our risk of infection, and even heart health.

Gut microbiome – what to know

One word that floats around a lot in research about the gut is the microbiome. Simply speaking, the microbiome consists of thousands of tiny microorganisms that live in the intestines, all of which are essential for digestion – and, as it turns out, so much more.

The microbiome is made up of bacteria, viruses, fungi, and protozoa. These affect the nervous system, regulate hormone production, and produce neurotransmitters like dopamine and serotonin… which is where our gut microbiome links to sleep.

The gut and sleep

Just as our microbiome regulates sleep, sleep might actually regulate the microbiome. It’s thought that our circadian rhythms – the natural, 24-hour process that regulates the sleep-wake cycle – can affect the health of the microbiome.

What this means is that not getting enough sleep has the potential to seriously damage the function of the microbiome. One study found that people who were partially sleep deprived experienced a significant decrease in the beneficial bacteria in their gut, and even a decrease in insulin sensitivity.

·         The gut, sleep and cognitive health

There’s evidence to suggest that the effect of poor sleep on the gut might lead to cognitive decline.

One study in older adults found that those getting a better quality of sleep had higher levels of beneficial gut bacteria and better cognitive ability. Poor gut health may also increase levels of insomnia and depression. Sleepline covers this topic in more depth.

·         The gut, sleep and the metabolism

People who experience poor sleep quality, and wake frequently throughout the night, will find it difficult to reach deep REM sleep that’s needed for a healthy gut.

You might already know that restless sleep can lead to changes in eating patterns – but research has found that it may also increase the risk of obesity and metabolic disorders.

·         The gut, sleep apnoea and high blood pressure

It’s thought that sleep apnoea, a disorder that causes disrupted breathing in sleep, can negatively impact the gut microbiome. This damage is difficult to reverse, and may negatively affect all aspects of the body.

On the flip side, the gut itself might cause high blood pressure in people with sleep apnoea. This is why it’s so common for people with sleep apnoea to also have high blood pressure.

·         The gut, sleep and stress levels

One of the reasons why people struggle to sleep is because they’re experiencing high levels of stress. Interestingly, scientists think that stress can majorly affect gut health, while poor gut health can worsen our response to stress.

Studies have found that one particular beneficial gut bacteria can lower stress levels and promote restful sleep. It’s found naturally in the gut, as well as in fermented foods like yogurt.