If you’ve ever heard the term “gut feeling” or been told to “go with your gut”, you might have wondered how on earth your gut had anything to do with your thought processes. Up until recently, the answer would have been “absolutely nothing”. But new research has led scientists to believe that actually, the gut and the brain are connected in ways we never could have imagined.

The brain-gut axis

Your gut is often referred to as your second brain because of how strongly linked it is to your decisions, thoughts and feelings. This is due to the physical and biochemical connections between the brain and the gut, known as the brain-gut axis.

The gut and the nervous system

Neurons are most commonly thought of as being in the brain, and it’s true – we have billions of neurons located up in our brains for telling us how to behave in all situations. But we also have neurons in the gut, which link to our brains via the nervous system.

The vagus nerve is one of the biggest nerves connecting the gut and the brain. Studies have found that stress signals that are sent through this nerve can cause gastrointestinal problems like IBS and chron’s disease.

The gut and neurotransmitters

Your brain’s neurotransmitters produce chemicals that alter your mood and feelings. One neurotransmitter, serotonin, regulates your sleep cycle and affects your happiness levels.

These neurotransmitters are also produced by your gut microbiome. Studies have found that a less healthy gut microbiome is linked to irregular neurotransmitter production, which may affect everything from your mood to the quality of your sleep. Visit Sleepline for more information on the link between sleep and gut health.

The gut and appetite

The microbiome in your gut produces thousands of chemicals that affect how your brain functions.

When some of these chemicals are made in higher quantities, they can reduce appetite and cause you to naturally reduce your food intake. For this reason, scientists think that a healthy gut may be able to stimulate the brain to tell you when you’re full, helping with weight loss and healthier eating habits.

The gut and inflammation

Your brain and gut are also linked to your immune system. Your gut microbiota controls what passes into the bloodstream and what is eliminated from the body as waste, which is thought to play a key role in optimising the immune system.

The gut produces certain inflammatory toxins, and if your gut becomes leaky, it may produce too many of these toxins. When these pass into the blood, they can cause inflammation. This inflammation is linked to a number of brain disorders, such as Alzheimer’s and depression.

Using probiotics for brain health

Probiotics are beneficial gut bacteria that we can add to out diet for improving brain health. Some probiotics can improve the gut microbiome and result in decreased mental illness, like anxiety, depression and insomnia. Omega-3 fats, fermented foods like sauerkraut, and high-fibre, wholegrain foods can all benefit the gut and the brain.