Scientists have known for many years that the gut and the brain are linked. For instance, we know that psychological stress negatively affects gut function and that it is an important factor in the development of gastrointestinal issues like irritable bowel syndrome. More recently, there has been a growing body of evidence indicating that the gut microbiota plays a key role in how the gut and brain communicate. This has led to the concept of “microbiota-gut-brain axis” being established.
Scientific evidence accumulated in recent years from mice and human studies suggests that the gut microbiota affects some aspects of brain function and behaviour, including emotional behaviour.
In animal studies, germ-free mice or those with a severely disrupted microbiota had an abnormal response to stress, differing patterns of social interaction and alterations in cognition.
As for human studies, several have reported that patients with depression or anxiety have an altered gut microbiota. Evidence for the influence of gut microbes on the human brain include placebo-controlled trials suggesting that modulation of the gut microbiota may produce changes in mood or behaviour.
While the underlying mechanisms of the crosstalk between the gut microbiota and brain remain to be fully understood, several pathways have been identified, which include the vagus nerve, the immune system, the endocrine system, and bacterial metabolites and products. Short-chain fatty acids, which are metabolites produced by the gut microbiota, possess neuroactive properties and can initiate gut-brain signalling.
The gut microbiota also helps preserve gut permeability. Disturbances of microbiota balance, known as dysbiosis, may disrupt these pathways and trigger changes in the blood-brain barrier permeability, leading to not only gastrointestinal issues, but also, possibly neurological ones.
How Can We Shape Our Gut Microbiota to Help Support Gut-Brain Communication?
Until more is elucidated on the microbiota-gut-brain axis, we can strive towards healthy gut microbiota, which is important for gut and overall health.
Have a healthy diverse diet:
Diet is one of the key factors that influence the composition of the gut microbiota. A healthy lifestyle and maintaining a varied diet allow us to preserve the diversity and health of our microbiota. A greater diversity of microorganisms in the gut microbiota is directly correlated with gut and overall health and well-being. The more diverse the diet, the more diverse the microbiota. A diverse diet includes fibre-rich foods like vegetables, fruits, legumes, whole grains, as well as probiotic containing foods like probiotic yogurt.
Manage stress:
What we know from current research is that stress can induce significant changes in the gut microbiota composition and function, which can lead to intestinal inflammation and difficulties with digestion and issues related to the microbiota gut-brain axis. Some ways in which we can help manage stress include:
Mindfulness:
This practice allows us to become more present and less judgemental with our current physical, mental and emotional state. Being mindful has been shown to decrease stress levels, and we can practice mindfulness in a variety of ways such as practicing meditation, diaphragmatic breathing, gratitude, and journaling.
Seeking Support:
Seeking support and connection with loved ones and friends can help ease the burden of stress. Additionally, connecting with a therapist can allow you to better manage stress through learning effective coping skills.
Movement:
Movement has been shown to help decrease stress levels and in turn, boost our mood and behaviour. Movement can take many forms such as walking, dancing, running, weight lifting, cycling, and more! Do what works best for your body and what you enjoy.
Maintain proper sleep:
Sleep quantity and quality may contribute to gut microbiota diversity. Poor sleep has been linked to poor gut microbiota diversity, which in turn can affect our overall health. Seven to nine hours of good-quality sleep is recommended for adults.
In conclusion, while there is evidence that gut microbiota may influence our mood and behaviour, more research is needed to better understand how this happens. But one thing is for sure, our brain and gut are in constant communication, so we can all benefit from healthy lifestyle strategies to support our gut microbiota.
