Mind, Mood and Microbes: How the Gut and the Brain Talk to Each Other

You’ve probably heard the saying, “Trust your gut.” But did you know that your gut and brain are in constant conversation? This connection, known as the gut-brain axis, is important for your overall health. Let’s look at how this works and what you can do to keep both your gut and brain happy.

What is the gut-brain axis?

The gut-brain axis is a superhighway allowing information to pass between your gut and your brain. This connection involves nerves, hormones, and even the bacteria in your gut, all working together to keep things running smoothly.

The vagus nerve is the main road that connects your gut to your brain. It sends nerve signals back and forth, enabling the two to communicate.  What’s interesting is that 90% of the nerve signals travel from the gut to the brain, with only 10% of traffic running in the opposite direction. The brain depends on sensory information from the gut to assess our overall health and wellbeing.

Your gut produces hormones that tell your brain when you’re hungry, full, or stressed. In fact, 95 % of serotonin, which helps you feel happy and relaxed, is made in the gut. Good gut function is essential for optimal mood and brain function. 

It is estimated that there are 80 – 100 trillion bacteria and other microbes living in the gut. This is known as the microbiome.  Beneficial gut microbes help keep the gut-brain axis functioning properly and produce chemicals that can help us to regulate our mood.

How to keep your gut-brain axis healthy

The good news is that you can do a lot to support your gut-brain axis through simple diet and lifestyle choices.

Some foods can negatively impact the gut-brain connection. To keep your gut and brain in good shape you might want to avoid or limit:

Processed foods - are often high in unhealthy fats, sugars, and artificial ingredients that can disrupt the gut microbiome. Examples include: Fast food, chips, frozen ready meals and packaged snacks.

Sugary foods and drinks – a high sugar intake can feed harmful bacteria and yeast in the gut, leading to gut imbalances that may affect your mood and energy levels. Examples include: Fizzy drinks, sweets, cakes, and pastries.

Artificial sweeteners - studies suggest that artificial sweeteners can negatively alter our gut bacteria and may contribute to digestive issues. Examples include: Diet and sugar-free drinks and many products labelled “low-calorie” or “sugar-free.”

Refined carbohydrates – can spike our blood sugar levels and contribute to inflammation, which is bad for both the gut and the brain. Examples include: White bread, white pasta, white rice and many breakfast cereals.

Excessive alcohol - drinking too much alcohol can damage the gut lining, leading to “leaky gut,” where toxins and bacteria can enter the bloodstream, potentially affecting mood and brain function. Examples include: Beer, wine, spirits and binge drinking.

Avoiding or limiting these foods can help reduce the risk of gut imbalances that could affect your mood, energy levels and overall wellbeing and help you to maintain a healthy gut-brain axis.

Instead, I encourage you to focus on eating whole, nutrient-rich foods that support both your gut and brain, such as:

Fibre - fruits, vegetables and wholegrains are rich in fibre, which feeds the good bacteria in your gut and supports gut motility. Eating a diverse range of different coloured plant foods promotes a diverse array of beneficial gut bacteria, which is key for gut health.

Prebiotics are non-digestible fibres that feed the good bacteria in your gut, helping them to grow and thrive. Prebiotic-rich foods include:

·         Artichokes – roast them and have as a side dish or add to salads

·         Asparagus – grill, roast or steam as a side dish

·         Garlic – use in cooking, sauces and dressings

·         Green bananas – eat raw as a snack or add to smoothies

·         Leeks – use in soups, stews or as a cooked side dish

·         Oats – enjoy as porridge, in granola or in baked goods

·         Onions – add raw to salads or cook and add to various dishes

·         Wholegrains – include wholegrain bread, brown rice or quinoa in meals

Probiotics are live bacteria and yeasts that are beneficial for your gut health. They are found in the following foods:

·         Plain yogurt (with live cultures) – eat on its own, with fruit and granola or add to smoothies

·         Kefir (no added sugar) – drink on its own or blend into smoothies

·         Sauerkraut – use as a topping in sandwiches or as a side dish

·         Kimchi – add to rice bowls, salads or eat as a side

·         Miso – use in soups, dressings or marinades

·         Kombucha – drink as a beverage

Regularly including a variety of these prebiotic and probiotic-rich foods in your diet is a great way to promote a healthy gut-brain axis.

Polyphenols are potent anti-inflammatory foods with antioxidant properties. They help to improve microbial diversity and protect the brain against cognitive decline. Good sources of polyphenols include herbs and spices, berries, nuts and seeds, coffee, tea and dark chocolate. A diet containing a variety of polyphenol-rich foods can help to reduce inflammation in the gut and support overall health.

Omega-3 fatty acids are great for reducing gut inflammation and supporting brain health. Some foods that are high in omega-3 include oily fish like wild salmon, mackerel, sardines, herring and anchovies, as well as plant sources like walnuts, chia seeds and flaxseeds.

Simple lifestyle changes for a healthier gut and a happier brain

Beyond what you eat, your daily habits can also make a big difference:

·         Chronic stress can harm your gut, leading to digestive problems and mood issues. Try to regularly practice stress-relieving techniques like meditation, deep breathing or just going for a walk.

·         Good sleep is essential for a healthy gut. Aim for 7-9 hours a night to help your body and mind repair and recharge.

·         Regular exercise is a great way to boost your gut health. It increases the diversity of your gut bacteria and is good for both your body and mind.

Looking Ahead

Scientists are just beginning to understand the full impact of the gut-brain axis, but one thing is clear: Taking care of your gut can help you feel better both mentally and physically. By making a few simple changes to your diet and lifestyle, you can support this important connection and improve your wellbeing. So listen to your gut - it might be telling you more than you think!