The Gut Brain Connection
Article by Olive Rosenvinge
The gut plays a crucial role in maintaining both our physical and mental health. It’s crucial we maintain a healthy gut, as it has so many far-reaching benefits.
Why is the gut-brain connection so important?
We used to think that that the gut and the brain communicate from top to bottom. But we now understand that it’s actually more of a bidirectional relationship.
Our gut microbiota, (the trillions of microbes living in our gut), have a highly influential role in how our brain operates.
When we talk about the gut-brain relationship, we should really think of it as a relationship between the microbiota, the gut, AND the brain.
A lot of the communication between our gut and brain depends on the ‘chatter’ from these trillions of microbes living in our gut.
You may know that the brain has billion of nerve cells (neurons), which send messages all over the body allowing you to do everything from breathing to talking, eating, walking and thinking.
The gut communicates with our body in a similar way. In fact, it has 500 million nerve cells.
So how does to gut and brain ‘speak’ to each other?
One of the main pathways that our microbes, gut and brain use to ‘speak’, is via the nerve pathway.
They use chemical messengers called neurotransmitters.
The neurotransmitters govern the different physical processes and emotions happening in our gut and brain.
This means these neurotransmitters can have a significant influence on both our physical and mental wellbeing.
So, the neurotransmitters produced in our brain, which are secreted and managed by our gut, are the main ‘language’ used in our body.
It’s often surprising for many people when they find out that our gut produce some of the same neurotransmitters that our brain does.
Serotonin
Did you know that 90-95% of the body’s overall production of the neurotransmitter Serotonin (the happy neurotransmitter) is produced and managed in the gut?
Within the brain, Serotonin plays a huge role in our mood and cognition.
In our gut, Serotonin is related to processes such as motility through the digestive system.
This means that our gut microbiota can directly and indirectly influence serotonin levels.
Serotonin is produced in special cells called EC cells. These cells are found on the lining of our gut.
It’s the role of our microbes in our gut to ‘switch’ these cells on to produce the serotonin for our body.
The gut can also have an influence on the serotonin in the brain.
Tryptophan
Have you heard of tryptophan?
It’s an amino acid, which can cross the blood-brain-barrier.
Within the brain, the tryptophan gets converted into serotonin.
We think that the gut may also have some control over the availability of tryptophan.
Tryptophan is found in a wide variety of protein-rich foods. Things like turkey, chicken, eggs, oily fish, and pumpkin seeds.
Dopamine
Dopamine is another neurotransmitter. 50% of it is produced in the gut.
Within the brain, dopamine is associated with the pleasure and reward system. But dopamine also plays a role in gut function.
This just shows how much of an impact our microbiota plays in supporting the health of our brain.
Nutrition
But remember, to make sure we maintain a happy and healthy gut and seemingly, a happy mind, we need to consider our diet as well as external factors like stress.
Whilst nutrition might not be the only answer to improve mental health, it can definitely provide powerful support, and unfortunately, many of us overlook it.
Chickpeas
Chickpeas are rich in both protein and zinc.
A diet which is high in zinc contributes to GABA. This is a key neurotransmitter in the brain. It blocks signals to reduce stress, worry and anxiety.
Citrus
Citrus is a great way to get lots of antioxidizing vitamin C.
Many neurodegenerative diseases are connected to oxidative stress, so getting lots of antioxidants through foods like oranges, lemons and grapefruit are great.
Banana
Bananas are high in a fibre which is not digested in the gastrointestinal tract. Instead, it reaches the large intestine where it feeds the friendly bacteria living there. By feeding them, they produce short-chain fatty acids, contributing to digestive health.
Kimchi
Fermented foods are probiotic food which provide good bacteria to nourish the gut. These good bacteria are important in a number of healthy bodily functions, from producing certain vitamins, improving digestion and gut health, to helping to fight infection.
Walnuts
Walnuts are a rich source of healthy fats. Walnuts are high in DHA, folate, Omega-3s which feed the key hormones that controls neuroplasticity.
Because nuts are high in fibre and have a high concentration of antioxidants, they are great for gut health. Walnuts have been associated with better brain health, and lower levels of depression.
This blog post was written by Olive Rosenvinge. Olive has a first class degree in Food Science and Nutrition from the University of Leeds and looks forward to a future career helping people to eat better to maximise our quality of life and debunking nutrition myths. Her interests and hobbies include running, cooking and often hosting weekly dinner parties and events for her family and friends. You can find her on Instagram @lusciouslylivs.