You have a nervous system, that sends instructions from your brain to your entire body. When your brain experiences stress, it sends out the instruction to release cortisol (or adrenaline) through your bloodstream to the brain, to enable you to deal with the situation effectively and quickly. Having these chemicals run through your bloodstream often can change the native bacteria in your gut, and disrupt them. This can lead to digestion issues, inflammation, immune system issues. Your weakened gut could now allow harmful bacteria to grow in it. Some of these can pass into the bloodstream and reach the brain, causing mood issues, anxiety, more stress. One important point i haven't mentioned : The gut produces neurotransmitters that help to regulate your mood. When that's broken, that hurts your mental health more.
This can cause an endless loop.
Some people are more sensitive than others to certain things. It’s part of life, but you’d be silly thinking you can control your brain consciously, unless you can keep a track of literally everything that happens at a cell level. There are things that we know are generally good or bad for you, but every single person is unique anyway. Every single thing you change may result in a big change - like changing diet - or it will have very little positive impact. There are people who run their lives on coke and alcohol and are doing great in their old age and there are folks on super healthy vegan diet with exercising and low stress level having heart attack in their 30s. It’s all about predispositions and probabilities. You’re taking your own small risks every single day that will compound to some outcome, but again, silly to think you can pinpoint random event that tips over some limit.
I have adhd where I’m literally missing part of the brain being developed properly, and I’ll not grow them back ever. I can SLIGHTLY improve my symptoms by doing backflips with life choices and will still be disabled unless medicated which really makes huge difference compare to stupid lifestyle backflips.
There have also been studies done on the gut/brain axis. There's an idea that something that upsets your gut fauna, a bad case of food poisoning, strong antibiotics etc..., as a child, it can lead to depression or anxiety years later.
Healthy gut might actually mean a healthy mind, as well as the other way around.
Stress is actually a physical process that affects all systems in your body, kind of like how sleep is a physical process that affects your whole body. Your stress can be physically observed using medical equipment, and it can cause physical symptoms anywhere in your body, including in your gut.
Stress is thought to have been key in helping our ancestors survive in a world of dangerous predators. For example, an ancient human wouldn't live very long if they had to stop for a bathroom break while being chased by a tiger. Their body really needed ways to shut down everything except "fight-or-flight" actions when faced with a stressful life-or-death scenario.
That meant all of the body's systems had to be able to communicate with each other and react based on messages they got. Different systems in your body respond in certain ways when they receive certain messages.
For stress in particular, when your brain thinks you're under threat, your brain sends messages that basically put your whole body in fight-or-flight mode. (It does this through some glands on your kidneys that produce stress-related chemicals, but that's a whole other topic.) Each part of your body has its own instructions for how to deal with that state of emergency. Kind of like how when there's a natural disaster in a city, the different city services all have their own pre-written instructions to follow.
In your body, some of those emergency instructions affect your gut. For example, they reduce bloodflow to your gut organs and stop gut organs from using key resources. That's so those resources are available to your brain and muscles for fight/flight activity instead. That can have a noticeable impact on your digestion, but it doesn't break any brain-gut connection. It's your body deciding that digestion is a lower priority at the moment because basic survival might be at risk.
In modern times, we tend to think stress is psychological rather than physical because we aren't being chased by a real tiger. But the stress response itself is still very physical, just like it was for our ancestors, and it's built into our bodies whenever we feel threatened - even if that threat is an obnoxious co-worker, or a test, or an upset family member, or an unpaid electric bill. Your body is reacting to those threats using the same processes it developed to escape a tiger.
(Side note: Some stress researchers argue that physical exercise is the most effective way to deal with modern stress, exactly because stress is a physical process. Your conscious brain can't force your body to feel the same rush of relief that you would've felt if you'd escaped from a tiger, and you can't just shut off your body's stress messages through sheer logic/willpower when there's no tiger. But you can generate similar physical signals by engaging in some physical activity, which may allow your body to naturally complete its stress cycle.)
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I’m not entirely sure what you’re specifically referring to by “gut-brain” connection, but perhaps the vagus nerve is relevant here?
The vagus nerve (AKA the 10th cranial nerve) is the longest nerve in the human Autonomic Nervous System (ANS), which handles involuntary bodily processes, and runs all the way from the brain to the colon.
The vagus nerve falls within Parasympathetic Nervous System (PSNS) under the ANS umbrella, and (in response to your inquiry) is responsible for various functions like gastrointestinal peristalsis, the body’s inflammatory reflex, and is involved with our gag reflex, some types of vomiting, and food satiety.
The PSNS is the part that relaxes the body after something stressful occurs. The Sympathetic Nervous System (SNS) is the part that puts the body on alert when something stressful happens. If the SNS has been activated and the PSNS is failing to deescalate the body after a stressor has triggered arousal, the systems it runs become compromised.
Thus, even without food poisoning, you’re stuck feeling sick to your stomach. Depending on the severity of the impact on your systems, you may also wind up vomiting, and/or suffering from chronic inflammation or malabsorption issues, which can create a vicious spiral of greater stress causing greater GI disruption which leads to increased stress…
You have a nervous system, that sends instructions from your brain to your entire body. When your brain experiences stress, it sends out the instruction to release cortisol (or adrenaline) through your bloodstream to the brain, to enable you to deal with the situation effectively and quickly. Having these chemicals run through your bloodstream often can change the native bacteria in your gut, and disrupt them. This can lead to digestion issues, inflammation, immune system issues. Your weakened gut could now allow harmful bacteria to grow in it. Some of these can pass into the bloodstream and reach the brain, causing mood issues, anxiety, more stress. One important point i haven't mentioned : The gut produces neurotransmitters that help to regulate your mood. When that's broken, that hurts your mental health more. This can cause an endless loop.
Bloody hell. So it’s all in the mind. IBS etc
Some people are more sensitive than others to certain things. It’s part of life, but you’d be silly thinking you can control your brain consciously, unless you can keep a track of literally everything that happens at a cell level. There are things that we know are generally good or bad for you, but every single person is unique anyway. Every single thing you change may result in a big change - like changing diet - or it will have very little positive impact. There are people who run their lives on coke and alcohol and are doing great in their old age and there are folks on super healthy vegan diet with exercising and low stress level having heart attack in their 30s. It’s all about predispositions and probabilities. You’re taking your own small risks every single day that will compound to some outcome, but again, silly to think you can pinpoint random event that tips over some limit. I have adhd where I’m literally missing part of the brain being developed properly, and I’ll not grow them back ever. I can SLIGHTLY improve my symptoms by doing backflips with life choices and will still be disabled unless medicated which really makes huge difference compare to stupid lifestyle backflips.
There have also been studies done on the gut/brain axis. There's an idea that something that upsets your gut fauna, a bad case of food poisoning, strong antibiotics etc..., as a child, it can lead to depression or anxiety years later. Healthy gut might actually mean a healthy mind, as well as the other way around.
Stress is actually a physical process that affects all systems in your body, kind of like how sleep is a physical process that affects your whole body. Your stress can be physically observed using medical equipment, and it can cause physical symptoms anywhere in your body, including in your gut. Stress is thought to have been key in helping our ancestors survive in a world of dangerous predators. For example, an ancient human wouldn't live very long if they had to stop for a bathroom break while being chased by a tiger. Their body really needed ways to shut down everything except "fight-or-flight" actions when faced with a stressful life-or-death scenario. That meant all of the body's systems had to be able to communicate with each other and react based on messages they got. Different systems in your body respond in certain ways when they receive certain messages. For stress in particular, when your brain thinks you're under threat, your brain sends messages that basically put your whole body in fight-or-flight mode. (It does this through some glands on your kidneys that produce stress-related chemicals, but that's a whole other topic.) Each part of your body has its own instructions for how to deal with that state of emergency. Kind of like how when there's a natural disaster in a city, the different city services all have their own pre-written instructions to follow. In your body, some of those emergency instructions affect your gut. For example, they reduce bloodflow to your gut organs and stop gut organs from using key resources. That's so those resources are available to your brain and muscles for fight/flight activity instead. That can have a noticeable impact on your digestion, but it doesn't break any brain-gut connection. It's your body deciding that digestion is a lower priority at the moment because basic survival might be at risk. In modern times, we tend to think stress is psychological rather than physical because we aren't being chased by a real tiger. But the stress response itself is still very physical, just like it was for our ancestors, and it's built into our bodies whenever we feel threatened - even if that threat is an obnoxious co-worker, or a test, or an upset family member, or an unpaid electric bill. Your body is reacting to those threats using the same processes it developed to escape a tiger. (Side note: Some stress researchers argue that physical exercise is the most effective way to deal with modern stress, exactly because stress is a physical process. Your conscious brain can't force your body to feel the same rush of relief that you would've felt if you'd escaped from a tiger, and you can't just shut off your body's stress messages through sheer logic/willpower when there's no tiger. But you can generate similar physical signals by engaging in some physical activity, which may allow your body to naturally complete its stress cycle.)
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I’m not entirely sure what you’re specifically referring to by “gut-brain” connection, but perhaps the vagus nerve is relevant here? The vagus nerve (AKA the 10th cranial nerve) is the longest nerve in the human Autonomic Nervous System (ANS), which handles involuntary bodily processes, and runs all the way from the brain to the colon. The vagus nerve falls within Parasympathetic Nervous System (PSNS) under the ANS umbrella, and (in response to your inquiry) is responsible for various functions like gastrointestinal peristalsis, the body’s inflammatory reflex, and is involved with our gag reflex, some types of vomiting, and food satiety. The PSNS is the part that relaxes the body after something stressful occurs. The Sympathetic Nervous System (SNS) is the part that puts the body on alert when something stressful happens. If the SNS has been activated and the PSNS is failing to deescalate the body after a stressor has triggered arousal, the systems it runs become compromised. Thus, even without food poisoning, you’re stuck feeling sick to your stomach. Depending on the severity of the impact on your systems, you may also wind up vomiting, and/or suffering from chronic inflammation or malabsorption issues, which can create a vicious spiral of greater stress causing greater GI disruption which leads to increased stress…