Sleep: why it’s important for our gut

Did you know that just 2 nights of disturbed or reduced sleep can affect the composition of your gut microbiome (which is the trillions of microbes living within your large intestine associated with a wide range of health benefits). Given that 1 in 3 adults are reported to have some form of insomnia at some point in their life, this means that there could be an awful lot of us with gut dysbiosis (an imbalance of good/bad gut bugs).

What does this mean for our gut?

Essentially, tired microbes can’t do their jobs properly which can lead to troublesome gut symptoms (bloating, altered stool habits and more) as well as increased inflammation and stress hormones in the body. This can happen regardless of diet, and so sleep hygiene is something that I talk about with many of my clients, especially if they have Irritable Bowel Syndrome (IBS). 

It’s a two-way street when it comes to sleep and our gut health. Just like poor sleep can negatively impact our microbial diversity, our microbial diversity can affect total sleep time as well as sleep quality. This means that if we have poor dietary diversity we may be contributing to reduced sleep quality. The good news however is that if we take care of our gut microbes by feeding them well with plenty of different types of fibre, we could see an improvement in sleep issues as well as our mood. 

Diet approaches for improving sleep


In our waking hours we can focus on plant-based diversity to feed our microbes. The concept of 5-a-day focuses only on our fruits and vegetables when actually our microbes benefit from so much more. Ideally we want to give them 30+ different types of plants per week, which has been scientifically shown to positively affect our gut microbiome. 

Without being too prescriptive, because each day will be different, aim for:

  • 2-3 pieces of fruit (spread the intake out across the day)
  • 5-7 types of vegetables/salad (e.g., 3 and lunch and 4 at dinner)
  • 3 types of wholegrains (wholewheat pasta, quinoa, buckwheat, oats) 
  • 1-2 portions of nuts (or nut butters) and seeds
  • 1-2 types of legumes (beans, chickpeas and lentils)
  • Herbs & spices 

In my experience seeing clients in my clinic, it’s the legumes, nuts and seeds that most people are falling short on. My top tips for getting these in the diet to begin with are: 

  • Add a handful of lentils to a bolognese, soup, or casserole. 
  • Instead of plain baked beans, mix in a tablespoon of tinned mixed beans (some manufacturers now do 5 bean products)
  • If you’re not a fan of snacking on whole nuts and seeds, blend some up and store in a container to use as sprinkles onto breakfast or yoghurt. 


It’s also important to consider caffeine intake. Everyone metabolises caffeine differently (did you know you can test your DNA to find this out? It’s something that I offer in my clinic). Caffeine can stay in our body for 6 hours, so reducing the amount you have in your day, and perhaps aiming to go caffeine free after lunch can be a good move. Remember that caffeine isn’t just from tea and coffee it is also present in green tea, chocolate and colas. 

Meal Timing

Studies have shown that the timing of our meals can affect our circadian rhythms, which are 24-hour cycles that are part of the body’s internal clock. Our body clock is sensitive not just to daylight, but also to being fasted or fed. If we’re often changing our meal times or eating particularly late, we risk disrupting our circadian rhythm which can impact the hormones involved in metabolism and lead to imparied glucose and lipid tolerance, which can contribute to the development of obesity and cardiovascular disease. This circadian rhythm misalignment can also play havoc with our bowels and lead to gastrointestinal disorders. This is something that shift workers often experience. 

My recommendation is to avoid eating late at night or within the early hours of the morning where possible. If you’re working a shift pattern, try to maintain a diverse diet where possible and still keep to a meal pattern if you can. We’ll try to do another post aimed specifically at this group of individuals in the future. 

Non-diet approaches for improving sleep


This can be a two-way process because lack of sleep can lead to feeling stressed, and stress can lead to a lack of sleep. Therefore, stress management is key, and this can look different for different people. Here’s some suggestions:

  • Create a calming environment before bed – keep the lights dim
  • Reduce the use of blue light i.e. no devices for an hour before bed
  • The optimal temperature for a bedroom is around 18 degrees Celsius
  • Consider trying to implement a practice of mindfulness or some breathing exercises before going to bed


This can be another vicious cycle as if you’re too tired you may be less likely to exercise. However studies have shown that moderate exercise during the day can improve sleep quality. You may want to play around with what type of exercise you prefer, but aim for around 30 minutes per day. 

You may also want to try some yoga, in particular Yin Yoga which is the less “active” form of yoga that is more calming and meditative and which can help release tension in soft tissues. 


A simple one, but it’s true that waking up and going to bed at the same time every day (including weekends) can help keep our body clock’s in balance. Getting some daylight early in the morning can also be beneficial for many. 

What about supplements?

Some research has found that certain probiotics may improve sleep quality however this doesn’t mean we should all start taking one – it’s important to remember that different probiotics do different things. Often a limitation when it comes to this type of evidence is that the strains of probiotics studied aren’t widely available in every country. For example Lactobacillus plantarum PS128 (PS128) is a widely studied type of probiotic known as a “psychobiotic” developed in Taiwan using fermented mustard greens. It’s not too tricky to find the species “Lactobacillus plantarum” but the strain “PS128” isn’t readily available in the UK.

When it comes to other types of supplements for sleep, apart from melatonin which isn’t available over the counter, unfortunately the evidence isn’t that conclusive, although I do discuss with my clients key nutrients such as vitamin D, magnesium and zinc which are all thought to have a role in sleep quality. However, correcting any shortfalls through diet would always be beneficial over supplementation, as then the microbes get fed with not only the fibre from the foods but also the polyphenols which are plant-based chemicals which have been shown to potentially help improve sleep quality and duration. 


When it comes to sleep, alongside some simple sleep hygiene principles, taking care of your microbes by feeding them well could lead to a reduction in sleep issues as well as improved mood. And by getting better sleep, we might be positively impacting our gut microbiome further leading to improvements in overall health. 

Book in to see me if you’re interested in optimising your gut health for your sleep where we can test some key nutrients and perhaps even your DNA to see if you really can have that extra cup of coffee or not!


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