How Your Gut Affects Your Brain
The diversity of your gut microbiome plays an important role in your health and wellbeing. From how you look and feel to your energy levels and cognitive abilities, what happens deep inside your gut affects your entire being. In recent times, deep links have been uncovered between the health of the gut and the health of the brain, with certain bacteria known to influence healthy brain function. Gut health also has a strong influence at the beginning of life, with researchers finding links between premature babies, brain damage, and the early development of the gut.
From the moment we take our first breath, our health is influenced by the microbes that live inside our gut. A healthy human gut includes Bacteroidetes, Firmicutes, Actinobacteria, Proteobacteria, Fusobacteria, and Verrucomicrobia. Overall, there are 160 species that make up the human gut, with these microbes functioning like an organ and weighing more than the brain. In fact, the gut is sometimes referred to as the enteric nervous system (ENS) or 'second brain', because it has such a profound influence on our behaviour.
The gut is involved in a direct line of biochemical communication with the brain, which is defined by special nerve cells and immune pathways. This gut-brain axis affects everything we do, with gut bacteria involved with making neurotransmitters such as serotonin. This relationship also goes the other way, with the brain sending signals back to the gut to control digestion. If these channels do not operate properly, the health of the brain can be affected. According to research conducted at the Wisconsin Alzheimer’s Disease Research Center, "people living with Alzheimer’s disease have a unique, and less diverse, community of gut microorganisms than their healthy counterparts."
We are learning more about the human gut all the time, with our traditional understanding often completely flawed. According to Jay Pasricha, M.D., director of the Johns Hopkins Center for Neurogastroenterology, our gut also infuences our mental health: “For decades, researchers and doctors thought that anxiety and depression contributed to these problems. But our studies and others show that it may also be the other way around... A higher-than-normal percentage of people with IBS and functional bowel problems develop depression and anxiety.”
According to another research paper, the early development of the gut, the brain, and the immune system are closely interrelated. Some researchers talk of the gut-immune-brain axis, with early gut diversity having a huge influence on the immune system. According to research from the University of Vienna, compromised gut diversity in premature infants may lead to a higher risk for brain damage: "In fact, we have been able to identify certain patterns in the microbiome and immune response that are clearly linked to the progression and severity of brain injury," said David Berry.
While there is a strong heritable component to gut microbiota, we can influence this environment through diet and exercise. Cruciferous vegetables and foods high in antioxidants are great for the gut, with a fresh and diverse diet helping to create a healthy and diverse gut. Along with food, exercise, sleep, and stress-reduction techniques can also help to regulate your metabolism and aid gut microbiota composition. Growing awareness of the gut highlights a significant shift in human health, as we slowly learn about the importance of diversity deep within the body.