Can Stress Trigger IBS Symptoms?
Reviewed by: HU Medical Review Board | Last reviewed December 2022
Stress is a common trigger of irritable bowel syndrome (IBS). Studies show that stress makes IBS symptoms worse. IBS can bring on added stress, resulting in a cycle that can feel never-ending.1
But how and why does stress trigger gastrointestinal (GI) symptoms like bloating, diarrhea, and stomach pain? It comes down to the fact that the brain and the stomach have a closer relationship than you might think.2
The gut-brain connection
In the last several years, more research has been done to study the connection between the brain and the gut. This connection is called the brain-gut axis.2 We all know that "butterflies in the stomach" sensation when we feel anxious or nervous. Finally, researchers are beginning to understand the meaning behind that saying. Recent research shows that the gut communicates to the brain and vice versa. Microbes that live in the gut communicate to the central nervous system through 3 different channels:2
- Nervous system
- Endocrine system
- Immune system
The brain can affect the gut's microbiome in many ways, such as:2
- Affecting the movement of muscles in the digestive tract (gut motility)
- Weakening of the gut lining (gut permeability)
- Changing the community of microbes and bacteria in the gut
- Releasing certain hormones into the gut
Any disturbance – for instance, stress and anxiety – can disrupt the microbiome environment and gut function.3
Stress and the vagus nerve
The vagus nerve – or vagal nerves – are the main nerves of your parasympathetic nervous system (PNS). The PNS regulates the "rest and digest" functions of your body – your heart rate, digestion, and immune system. These are involuntary functions, which means you cannot consciously control them.3,4
The nerve fibers within the vagal nerves send information to your brain, heart, and digestive system. The vagal nerves are crucial in the body's "rest and digest" responses.3,4
On the flip side, the sympathetic nervous system (SNS) – responsible for the "fight or flight" functions in the body – is activated by stress. When the SNS is activated, the vagal nerves are repressed and cannot communicate with the brain and gut like they are supposed to.3
If the vagal nerves are damaged in any way – by prolonged stress, chronic diseases like diabetes, or viral infections – it can cause issues with the communication between the brain and gut. This can impact how the gut digests and moves food through the GI tract. Over time, this can result in an abnormal vagal tone – which is present in a lot of people with IBS.3,4
There are several treatments that can help restore vagal tone. These include:3
- Vagal nerve stimulation (VNS)
- Dietary changes
- Prebiotics and probiotics
- Fecal microbiota transplantation
- Cognitive behavioral therapy
- Complementary therapies such as deep breathing, hypnosis, and meditation
How stress affects the gut
Stress may alter hormones and other parts of the brain. This can affect the brain-gut interactions and lead to changes to your body's GI tract. In addition, stress may alter the nervous system response, which can change the way a person responds to pain.1,3
Studies suggest that a key part in linking stress to increased gut permeability and changes to the gut environment may be corticotropin-releasing factor (CRF). CRF is a protein found in the CNS that triggers the body's hormone and behavioral response to stress. Therefore, increased levels of CRF and mild inflammation were found during stressful situations.3
Stress that becomes long-lasting (chronic) or overwhelming can become harmful to the gut. In a 2021 study, mental distress – including anxiety, depression, chronic stress, and poor sleep – was linked to GI issues including IBS.1
Ways to reduce stress
Reducing stress is an important aspect to controlling IBS symptoms. Consider doing the following to help reduce overall stress in your life:5
- Exercise – Regular exercise that gets the blood pumping is a great way to reduce stress and keep your body healthy.
- Acupuncture – An ancient Chinese medicine practice, acupuncture uses thin needles to stimulate blood flow. It can help with stress and pain.
- Massage – Massage can be a great pain reliever and stress reducer.
- Meditation – Meditation involves deep breathing and helps to lower your heart rate. It can be very restorative and relaxing and can help activate the PNS.
- Yoga – Restorative yoga and Yin yoga activate the body's PNS and can help restore vagal tone in the body.
- Psychotherapy – Talking with a therapist or counselor can help you cope with feelings of depression and anxiety.
If you are experiencing high levels of stress, talk with your doctor. They can help you find ways to handle stress in healthy, therapeutic ways.