Our ‘Second Brain’ – And Stress, Anxiety, Depression, Mood
Something amazing is hidden within the innermost layers of our digestive system. Experts have been knowledgeable about it for a long time, but modern technology is pushing the topic to the forefront. What is discovered there will change how we deal with our physical and mental well-being.
What occurs in our heads has a lot to do with what happens further south, in what experts playfully refer to as the “brain in our gut.” It has a strong link to the brain in our heads, and the two work together to influence our mental well-being and mood.
The brain in our gut, often known as our second brain, is composed of up of 200-600 million neurons that are grouped in the finely folded tissue that borders the gastrointestinal canal. With that kind of firepower, it’s no surprise that the gut does a lot more than just cope with meals and the harsher aspects of being human.
It is essential for psychological and emotional health since it sends data to the brain and directly affects things like stress, anxiety, and sorrow, as well as recall, decision-making, and learning. Although the brain in our gut is not able to process thought as we understand it, it interacts with our main brain in important ways that influence our emotional and mental wellness.
Unhappy thoughts. Unhappy stomach. Which happens first?
It’s obvious that depression, stress, and anxiety frequently result in irritable bowel syndrome, diarrhea, vomiting, abdominal pain, and pain. For many years, doctors assumed that stress, worry, and sadness were the root causes, but it now appears that the opposite is true. Irritation in the gastrointestinal tract appears to convey messages to the brain, causing changes in mood. This could explain why probiotics appear to reduce the signs of depressive disorders and anxiety.
The stomach plays an important role not just for physical health, but also for mental wellness. What interests me is the direction of impact. The vagus nerve is the longest nerve heading the brain (technically, it is one of 12 pairs of nerves that go from the brain). It travels from the brainstem to the stomach, passing through the heart and the most important organs along the route. Here’s the interesting bit. Approximately 90% of the vagus fibers transport information from the internal structures in the chest (such as the heart) and belly to the brain, not the opposite way around.
The fact that we were conversing about it before we even realized it is evidenced by the language we use. If you’ve ever made a decision based on your “gut instinct,” “went with your gut,” or “listened to your heart,” you’re probably receiving messages from this second brain in your tummy.
Without any question, the main channel of data transfer is from the gut to the brain. Messages can also move in the opposite direction, from the nervous system to the heart and the gut, and also through the vagus nerve.
The function of gut Bacteria.
The 100 trillion bacteria that have created a home in your gut, in addition to neurons, are another significant component in the gut-brain relationship. Emeran Mayer, a UCLA researcher of physiology, psychiatry, and behavioral sciences, claims that the bacteria in the gut possess extraordinary knowledge that is transmitted to the brain. Since the time we arrived on earth and possibly much earlier, they have had an impact on how we behave each second of every day.
A Wonderful Study: Extroversion to Introversion through the Gut
Mayer’s study demonstrated that particular combinations of bacteria in the stomach can influence brain circuitry, affecting traits like personality traits, mood, and cognition. Other investigators examined a possible link between gut bacteria and behavior and found some amazing results.
When the gut bacteria of fearful mice were put into the gut of extrovert mice, the extrovert mice felt more worried, according to one study. It also performed in the opposite direction. The fearful mice became braver and more extroverted after receiving the gut bacteria of the confident mice. When scientists altered their gut bacteria by offering them supplements or antibiotics, angry mice cooled down.
Additional Study: The Relationship Between Gut Bacteria and Temperament
There is evidence that some gut bacteria in young children, especially boys, correlate with temperament. The relationship was unaffected by past breastfeeding, diet, or delivery techniques. The results are as follows:
- More positive, interested, friendly, and energetic traits were seen in the kids with the most biologically diverse forms of gut bacteria.
- Extroversion in males was connected with a large number of specific types of bacteria (Rikenellaceae and Ruminococcaceae families, as well as Dialister and Parabacteroides genera).
- Self-control, cuddliness, and intense concentration were linked to a lesser diversity of gut bacteria in girls.
- Girls with a large number of a certain bacterial family (Rikenellaceae) appeared to be more scared than girls with a more healthy array of microorganisms.
Because this study is currently in its early stages, we don’t know what a healthy belly might look like in terms of gut bacteria mix, or exactly what variables could affect this. It is likely that the ideal microbiome balance will differ for every one of us. As a result, the investigators advise avoiding changing a child’s gut microbiome just yet.
Depression and the Gut.
Depression is commonly associated with a decrease in serotonin, a neurotransmitter that regulates mood. Surprisingly, only 5% of the body’s serotonin is kept in the brain. The gut stores the remaining 95% of the body’s serotonin.
It’s not shocking, then, that the most regularly used medications that act by modifying serotonin levels are frequently associated with gastrointestinal adverse effects. It’s also unsurprising that the gut may play a more significant part in depression than we now understand. This line of inquiry is still being pursued by researchers.
Anxiety and the Gut.
Young adults who consume more fermented foods which include probiotics have fewer social anxiety symptoms, according to a study. According to Professor of Psychology Matthew Milimire, “The probiotics in the foods that ferment are likely positively affecting the conditions in the gut, and modifications in the gut, in turn, affect social anxiety… the microorganisms in your gut may affect your mind.”
The relaxing factor and food.
We frequently reach for celery out of a desire for comfort. Pity. Instead, ‘comfort food’ is typically high in fat and high in energy.
The connection between food and our state of mind isn’t only in our brains. Yes, comfort food tastes and smells favorable, and it could remind us of moments when we were comfortable and safe, but there’s a lot more to it than that, as a group of Belgian experts discovered.
By using a nasogastric tube to supply nutrients to participants’ stomachs, the investigators hoped to eliminate the comfort food-related tastes, smells, and emotions. Either a fatty acid infusion or regular saline solution was administered to the subjects. Those who received the fatty acids experienced half as much sorrow and hunger as those who received the saline, while having no idea what they were getting through the tube. Brain scan results additionally showed this. Scans revealed increased activity in the area of the brain that regulates emotions very shortly after fatty acids entered the stomach.
Food and Stress
Early studies discovered that stressed-out rats preferred a higher-fat meal (peanut butter) over typical chow. Unsurprisingly, they gain greater amounts of weight than their less anxious colleagues. When under stress, the gut increases the manufacturing of ghrelin, a hormone that indicates appetite to the brain. Human studies have produced comparable findings. Following an altercation, couples were found to have significantly greater levels of the appetite-stimulating hormone, according to the latest research. The investigators stop short of claiming that relationships that fail lead to poor eating choices, but they do understand that there is a strong association.
There appears to be no doubt that one way stress affects behavior is through the gut, notably through the creation of ghrelin, which delivers information to the brain about hunger and choices for food.
Could gut bacteria be to blame?
Mayer notes the sharp increase in obesity, Parkinson’s disease, multiple sclerosis, and autism during the past 50 years. Each of these has affected the gut bacteria and the brain-gut connections. During the past 50 years, we have also seen a significant change in how we use medicines and how our food is grown and processed. Has our current method of operation caused the sudden increases? Although it’s still just speculation, this field of study is gaining popularity.
Where to now?
Our mental wellness is not just in our heads. Mental illness is neither. Finally, science is providing us with concrete evidence of this. There is no doubt that our gut health has an impact on our emotional and mental health. The discovery is interesting and has the potential to revolutionize therapies for a variety of disorders as well as the way we care for our psychological well-being.
The research is always changing but one thing is certain, it is essential to pay attention to the condition of the gut and do everything we can to maintain it healthy. It houses our second brain and may hold the key to our emotional and mental health.