Gut Health and Mood – The Gut/Brain Connection
gut health

Gut Health and Mood – The Gut/Brain Connection


Poor gut health has become increasingly more common thanks to modern day stress, increased consumption of processed foods, alcohol intake and medication use. While it’s well-known that the health of our gut has an influence on our digestion, what’s not so well known is the major impact it has on our mood and mental health too.

What is the gut-brain axis?

Our gut and brain are in constant communication. Linked by millions of nerves, this gut-brain connection creates a two-way street, allowing messages to be sent back and forth.

Known as the gut-brain axis, this unique connection means that the health of our gut has a large role to play when it comes to our mental health and brain function. Research shows that because of this two-way relationship, our gut microbiome has a powerful influence on our cognition, as well as impacts the risk of mood disorders, including anxiety and depression.

How gut bacteria affects the brain and body

Our gut microbiome is made up of around 100 trillion microorganisms, including bacteria, fungi and viruses. Around 1,000 different species of bacteria take up residence in the gut, with each having a special role to play when it comes to our overall health. These tiny gut microbes not only help with the digestion and absorption of our food, but also work to support a healthy immune system, good heart health, healthy body weight and good mood.

Things like a poor diet, excessive alcohol intake, high stress and antibiotics can upset the balance of good and bad bacteria in the gut. Known as dysbiosis, this imbalance in gut microbiota can lead to problems within our gastrointestinal tract, increasing the risk of issues such as irritable bowel syndrome as well as gut related immune disorders including ulcerative colitis and Crohn’s disease.

When it comes to the brain and mental health, evidence also suggests that imbalances in gut bacteria changes brain function, altering behaviour, cognition and even neurological development. While new research is constantly evolving, it’s thought that imbalances in the gut microbiome itself can contribute towards mental illness through the unique way the brain and the gut are connected.

What is the vagus nerve?

The vagus nerve is one of the largest nerves which connects the gut and the brain. Like a phone line, the vagus nerve allows messages to be sent back and forth meaning that not only can the brain affect our gut microbiome, but our gut bacteria can also directly affect the brain too. Research has shown that vagus nerve function is reduced in people with gut related disorders, such as IBS and Crohn’s disease, and further demonstrates the way that the gut and brain are closely linked.

Gut health and neurotransmitters

Neurotransmitters are types of chemical messengers that are produced by the brain to control things like mood and emotions, however many are also produced within the gut.

One example is serotonin. Known as our 'feel good' or 'happy hormone', serotonin is responsible for the regulation of our mood, as well as our sleep and appetite. Altered serotonin levels have been associated with low mood, depression and anxiety in some people. Considering over 90% of our body’s serotonin is made in the gut, it makes sense that any disruption in the microbiome can potentially cause mood related issues.

The gut microbiome and disease

Our gut bacteria play a strong role in our immune system, with research showing that alterations within the microbiome are linked to inflammatory and autoimmune diseases. When dysbiosis occurs, this can tend to weaken the gut barrier and can allow small food particles and toxins from food to pass through into the bloodstream which then triggers inflammation and an immune response. This is commonly referred to as 'leaky gut' or 'intestinal permeability'. When the gut barrier is 'leaky', it can result in issues such as food intolerances, bloating and skin issues, as well as risk of mental health disorders and cognitive decline. Further evidence suggests that changes in the way our gut microbes metabolise chemicals within the body can potentially lead to central nervous system disorders such as Alzheimer's disease and Parkinson's disease.

Tips for a healthy gut and mood:

There are many ways that we can support good gut health and a balanced microbiome. By consuming a healthy diet with a wide variety of fibre rich fruits and vegetables, including naturally occurring probiotic foods and managing stress levels, we can help to maintain a happy gut and a happy mood too. Top tips to support a healthy gut and brain include:

  • Reduce and manage stress levels. Research shows that stress directly impacts our gut bacteria, which can lead to dysbiosis and impact on our mood and digestion. Take time out for yourself, enjoy low intensity exercise such as walking and yoga, and try meditation and mindfulness techniques to reduce your stress levels.
  • Eat a variety of probiotic rich foods. Fermented foods such a sauerkraut, kimchi, miso, kefir and yoghurt are great sources of probiotics which helps to support a healthy and balanced gut microbiome. Research also shows that probiotic bacteria may help to improve symptoms of both depression and anxiety.
  • Include prebiotic and high fibre foods. Prebiotic and high fibre foods help the growth and activity of beneficial bacteria in the gut and may also help improve mood related issues. Eat foods such as bananas, apples, asparagus, leeks, as well as dark leafy green vegetables, nuts and seeds. Two Islands Happy Gut is a specialised gut powder formulated with a high dose of apple fibre, plus glutamine and soothing digestive herbs including slippery elm, marshmallow and chamomile. This unique combination helps to support a healthy balance of gut bacteria as well as works quickly to reduce bloating, regulate bowel motions and ease digestive discomfort.
  • Supplement with collagen. Collagen plays an important role in building and repairing the connective tissue that makes up our gut lining. Rich in amino acids glycine, proline and glutamine, supplementing with collagen can support digestive health by providing the building blocks needed to repair and protect the gut barrier. Our natural collagen production can be decreased by stress, so supplementing with a high-quality marine collagen may be of extra benefit for those feeling overwhelmed. Two Islands Marine Collagen Beauty Powder provides a high dose marine collagen, with at least 9g per serve. These highly bioavailable marine collagen peptides are easily absorbed and work to support a happy gut as well as healthy skin, hair and nails.

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