Gut and brain go together like coffee and crackers

While the gut and the brain are two distinct entities, they are intimately connected. This relationship is not only important for managing emotions and stress, but also for digestion. Due to the microorganisms, such as bacteria, fungi, and viruses, that reside in the gastrointestinal (GI) tract, each individual has a unique gut microbiome (environment). These microbiomes vary based on diet, lifestyle, and other factors, and they can affect various aspects of health, including appetite, weight, and even mood.

Tee said the trillions of microorganisms in the intestines perform crucial functions in the body, including the promotion of mental health. These microorganisms play a role in the stress response, mood, and cognition of the body. In other words, having a healthy gut and mind go hand-in-hand.

Tan noted that if the balance of the gut microbiome is breached, the body’s equilibrium will be tampered. This results in disruption of stomach acidity, intestinal alkalinity, and gut immunity. This can lead to digestive problems such as bloating, indigestion, heartburn, and inflammation of the bowel. As such, dietary choices and medications are the primary influences that can impact gut health, together with genetic factors. This is especially evident in people who suffer from eating disorders such as anorexia, bulimia, and binge eating.

Additionally, Tan highlighted the importance of being aware of, and understanding the signs of an unhealthy gut. “Poor digestion can manifest in various ways, such as bloating, stomach aches, diarrhoea, constipation, weight fluctuations, skin disorders, and even emotional disturbances.” If left untreated, these symptoms can lead to more severe conditions such as autoimmune problems and diabetes in the long run. Thus, being proactive about gut health and taking steps to improve it can have significant benefits for overall health and wellbeing.

Why is the gut important in mental health?
The gut, which is commonly referred to as the second brain, plays a crucial role in promoting mental health as a whole. This is because the enteric nervous system, which controls the gastrointestinal tract, uses the same neurons and neurotransmitters as the central nervous system to communicate with the brain. This indicates that the gut and the brain are constantly communicating and influencing one another’s function in real time.

In the example of the “fight or flight” response, the enteric nervous system responds by slowing digestion and redirecting more energy to the threat-causing situation. This interdependence is bidirectional, as the current emotional state can also have a significant effect on the digestive system. Tee noted that people suffering from depression, anxiety, or stress may develop gastrointestinal symptoms that include abdominal pain, bloating, indigestion, stomach cramps, constipation, and diarrhoea.

Ageing affects the axis
As one ages, their bodies must adapt to a variety of changes, such as bones losing density and strength, and muscles losing endurance and pliability. Similarly, the microbiome of the gut will need to adapt to accommodate the overall body changes. This includes the oesophagus moving more slowly, the stomach walls becoming thinner, and the output of stomach juice decreasing over time. These specific factors will affect the body’s ability to digest food and convert it into energy, necessitating that older people pay closer attention to their daily routines and make dietary modifications.

In addition, ageing can also tip the balance of bacteria in the gut, leading to an increase in pathogenic bacteria and a loss of diversity. This is why diseases such as reflux or peptic ulcer disease, inflammatory bowel disease, and colon cancer are prevalent in older people. The ageing process can also affect muscle movement, resulting in potentially unpleasant symptoms such as constipation, faecal soiling, incontinence, and perineum itching. Tan said there was no need to overly worry about things that are out of control but rather to mitigate these problems by prioritizing overall health. “As the saying goes, you are what you eat, so it is always important for us to be mindful of our food, regardless of our age.”

It boils down to diet and lifestyle again
The good news is that gut health can be positively changed with proper food choices. As such, maintaining a high-fibre diet, including both soluble and insoluble fibre, and limiting foods high in fat and sugar is crucial. “Adopting a healthy lifestyle by exercising regularly, avoiding smoking and alcohol, and limiting caffeine intake can contribute to a healthy gut,” said Tan. In addition, by incorporating prebiotics and probiotics into one’s diet, a healthy gut microbiome can be created. Probiotics play an important role in helping to digest complex food thus aiding digestion. Prebiotics are high-fibre foods that serve as a vital source of nourishment for the body’s microbes, ensuring that our digestive system stays healthy.

Keeping oneself happy by going outside, spending time with loved ones, or getting enough rest can also be helpful for one’s gut and mental health, said Tee. He added that activities that bring joy cause the brain to release dopamine, which triggers a sensation of pleasure. This contributes to mental wellbeing and, coupled with a balanced, healthy diet, goes towards maintaining the gut-brain axis.