The Stress Resilient Mind Blog
Mindfulness Training Helps IBS
Publication date: 16 January 2012
Recently I came across a new research paper showing efficacy of mindfulness training for Irritable Bowel Syndrome (IBS) – see also this other paper on mindfulness for IBS.
The researchers identified the likely mechanism as “non-reactivity to gut-focused anxiety and catastrophic appraisals of the significance of abdominal sensations” – in other words to a change in attitude on the part of the subjects towards their own gut sensations, and to the thoughts they had about them (though the thoughts themselves didn't necessarily change).
Does this mean that either the IBS itself is all in the head (brain, rather than imagination), or alternatively, that the improvement is all in the head and nothing to do with the gut itself? After all, IBS tends to be the diagnosis you get when your doctor can't find anything wrong with your gut.
I would argue no to both questions. The relationship between mind, brain and gut is a fascinating one, and very complex, so I thought it would be interesting to write a post about it. There's lot of research on IBS, suggesting multiple causal factors, and not necessarily the same ones between different individuals.
It turns out that brain and gut have a strong and complex two-way dialogue.
First let's consider how the brain affects the gut. The fact that we can't consciously control our digestion gives us a strong clue: the main mediator of brain to gut communication is the Autonomic Nervous System (ANS). The ANS has two branches: the sympathetic and the parasympathetic nervous systems. The former is in a general sense the accelerator with regard to the body. It's the mediator of the fight-or-flight response, which kicks in when we get anxious, but also when we get excited. The parasympathetic effect is sometimes known as the rest-and-digest response. So broadly, stress (sympathetic) tends to switch off digestion in favour of channeling resources towards more immediate needs (i.e. action). For example, digestive secretion (of stomach acid, digestive enzymes etc.) is inhibited, which is why it's not a good idea to eat when stressed or rushed. The normal contractions of the gut are stopped or reduced. Just to complicate things, the stress response when acute can hurry on the lower part of the digestive tract, as I noticed last week while walking in the countryside, through fields of sheep. This is the reason humans tend to suffer diarrhoea before job interviews, etc.
Relaxation tends to switch digestion back on again.
Stress hormones such as cortisol are also part of the relationship between stress and GI function.
Good quality research does indeed show that stress is a causal factor in IBS, and that IBS patients tend to be sympathetic dominant. But it may be that IBS sufferers have intestines that are disproportionately sensitive to stress. Trauma in early life predisposes people to IBS, perhaps by causing hyper-reactivity in either the ANS or the gut itself.
Gastric and intestinal ulcers were once thought to be caused by stress, till Australian pathologists Robin Warren and Barry Marshall showed they were caused by a bacterium, Helicobacter pylori, winning a Nobel prize in the process. A nice simple result, and a triumph for reductionist science. Except that most people with H. pylori in their guts don't get ulcers, and even worse, some people with ulcers don't have H. pylori. To cut a long story short, H pylori is only one causal factor, and another is stress (as the research clearly shows).
See 'Why Zebras Don't Get Ulcers' by Robert Sapolsky for a fuller discussion of the link between stress and GI illnesses.
What about the other half of the story: gut to brain communication? The first thing to say is that gut problems such as constipation, diarrhoea and IBS are themselves sources of stress, which will affect the brain in a complex inter-relationship. But there's much more to it. The vagus nerve is one of the most important in the body, and it transmits parasympathetic signals to the body, but also carries sensory signals in the opposite direction. The brain's job is to regulate the organism both internally and externally, so it's no surprise that the brain takes in a lot of information from the body.
Another major pathway is the immune system. Immune cells need to communicate in order to conduct orchestrated responses, and they do so (at least in part) by secreting molecules called cytokines. It turns out that brain and nervous system cells have receptors for cytokines, and in some cases the same molecules are used by nerve cells as neurotransmitters. In other words, there is widespread interaction between the immune system and the nervous system, which is the field of study of the relatively new and exciting science of psychoneuroimmunology.
Where does the gut fit into this? Well, the majority of the immune system's cells are found in the lining of the gut – perhaps 70% or more. This makes sense as the gut is the most likely point of contact with micro-organisms – present naturally in food. In fact the immune system's exposure to micro-organisms in the gut is the major determinant of both its development and its activity. The immune system needs to learn the difference between harmless and also beneficial bacteria and pathogenic species. That's why the gut flora is so important to health generally – not just gastrointestinal health. Unhealthy or imbalanced gut flora can predispose the immune system to inflammatory responses, and even auto-immune responses where the immune system attacks the body's own cells.
This is far too big a topic to do justice to here, so I'll round off with a practical point.
IBS is a classic example of an illness needing an integrated, multi-pronged approach to therapy. With my IBS clients I'm definitely thinking about mindfulness, biofeedback and other stress management methods, but I'd also (ideally) want to know what's going on in the gut itself. How are the digestive secretions? How is the gut flora? Answering these questions requires functional laboratory testing, the sort of thing the NHS standardly doesn't do (IBS is a functional disorder in which many mainstream diagnostic tests don't show anything wrong).
THE STRESS RESILIENCE BLUEPRINT
I've created a summary statement of what everyone needs for effective stress management: how to work with anxiety, panic, irritability, fatigue, insomnia, brain fog, low mood and other stress-related symptoms.
This plan is a blueprint of what my services and products aim to deliver.
Sign-up to receive a one-page summary and watch a short video commentary.Get The Stress Resilience Blueprint
READ MORE ABOUT BIOFEEDBACK FOR STRESS MANAGEMENT
How To Manage Your Mind With Biofeedback & Mindfulness
Book by Glyn Blackett
- Underlying dynamics in stress & anxiety
- Science of the mind-body connection & how it can be applied
- Why breathing is at the heart of stress management
- Practical models for framing self-control challenges & solutions
Like what you read here?
This article is part of a series - you can sign up to receive the whole sequence over the coming days. You'll also get new articles as they appear.