Some days have teeth. They’re the ones that push and pull and bite, and ask more of us than we have to give. A little bit of stress can be a good thing, nurturing resourcefulness and resilience, but when stress lasts for too long it can do damage.

One of the ways it does this is by interfering with sleep and stealing the healing, restorative pillow time that is essential for strong physical and mental health. New research has found something that can help.

The research, published in the journal, Frontiers in Behavioral Neuroscience, found that a regular intake of prebiotics can protect against the effects of stress, and restore healthy sleep patterns after a stressful event.

Prebiotics are different to probiotics and we need both for good physical and mental health. Both help the growth of healthy bacteria in the gut, but they work in different ways. Probiotics are living good bacteria that are important for a happy gut. They are found in cultured or fermented foods including yoghurt, sauerkraut, miso and kombucha. Prebiotics are food for probiotics. They are the non-living ingredients that feed the good bacteria and help them to flourish. Prebiotics are found in non-digestible plant fibres such as legumes, asparagus and oats, chicory, onions, leeks, garlic, Jerusalem artichokes.  

The connection between gut health and mental health has been well established. Inside our gut, in the intricately folded tissue that lines the gastrointestinal tract are 200-600 million neurons. This is affectionately referred to as ‘the brain in our gut’ or our ‘second brain’, and it plays a vital role in our mental health. It communicates back and forth with our main brain, directly influencing many aspects of our well-being, including stress, anxiety and sadness, as well as memory, decision-making and learning. 

While there has been plenty of attention on the importance of probiotics for mental health, there has been less on the role of prebiotics.

About the research.

The research was conducted with rats, but stay with me – rats and mice are often used in experiments because of their biological and physiological similarity to humans. In the study, the rats were divided into two groups. One group received a prebiotic diet for several weeks before they were exposed to stress. The other group did not receive the prebiotic-enriched diet before the stress exposure.

‘Acute stress can disrupt the gut microbiome and we wanted to test if a diet rich in prebiotics would increase beneficial bacteria as well as protect gut microbes from stress-induced disruptions. We also wanted to look at the effects of prebiotics on the recovery of normal sleep patterns, since they tend to be disrupted after stressful events.’ – Dr Agnieszka Mika, postdoctoral fellow and one of the authors of the study.

The stress that the rats were exposed to was equivalent in intensity to something like a car accident or a death of a loved one for humans.

The rats that were given the prebiotic diet did not show stress-induced changes in their gut mictrobiota. Their sleep patterns were also restored to normal sooner than the mice that did not receive the prebiotic diet.

We know the importance of keeping our stress levels in check, but at many times in our lives, stress will be unavoidable. Including prebiotics (as well as probiotics) in our diets might be a way to look after ourselves, and minimise the intrusion stress into our sleep and our daily lives.