Stress - Does it impact your gut microbiome?

In today's society, stress is a huge part of everyday life. But how does stress impact our overall health and our gut microbiome? And what can you do if there are too many stressors in your life? 

Stress is an inevitable part of life. But if you are chronicity stressed, it is not good for your health. In fact, chronic stress is a known risk factor for many disorders, including gastrointestinal disorders such as IBD and IBS. Additionally, it is also a promoter for common gut issues such as abdominal pain, indigestion, and heartburn. 

There are many causes of stress, both environmental, physical, and psychological. For instance, some common stressors are:

• a heavy workload
• sleep deprivation
• excessive exposure to electronic devices
• high consumption of caffeine
• negative emotions

Stress and the nervous system 

The nervous system is the main system of the body in charge of regulation and control of a vast number of bodily functions, as well as the communication between them.

The autonomic nervous system regulates the activities you do without thinking about them, such as regulation of the heart rate, blood pressure, and digestion. It is divided into the sympathetic nervous system (fight-or-flight) and the parasympathetic nervous system (rest-and-digest). 

Stress activates the sympathetic nervous system and triggers a fight-or-flight response, which results in a state of overall elevated activity and attention. In this state, the body's digestive system is downregulated and the production of stomach acid is limited. The body's ability to digest food is therefore reduced. Therefore, chronic stress can lead to gut issues, such as stomach pain, nausea, heartburn, diarrhea, and constipation.  

The gut-brain axis

The communication between the gut microbiome and the brain is extremely complex through the gut-brain-axis. 

Stress causes the release of stress hormones, inflammation, and autonomic alterations (e.g. changes in heart rate, body temperature etc.). This promotes an alteration of the gut-brain-axis and can lead to inefficient communication and affect the function of the systems in the body.

Stress and the gut microbiome 

Through the gut-brain-axis, stress can disturb the microbiome and reshape its composition. Stress is also considered as a promoter for dysbiosis; an imbalance between the beneficial and non-beneficial bacteria in the gut microbiome. 

• lower levels of the beneficial Lactobacillus (known for its probiotic functions, such as strengthening the immune system)
• higher levels of the more harmful Clostridiales

In addition to this, stress can increase gut barrier permeability, known as “leaky gut”. These are openings in the gut barrier, where bacteria and other compounds can leak through and into the bloodstream. Leaky gut has negative effects on the host, such as being a promoter for inflammation.

Can your gut microbiome impact your response to stressors?

Your gut microbiome may affect how you react to the stress in your life. Studies suggest that a disturbed gut microbiome can upregulate stress responsiveness. This means that you may be more sensitive to stressors and respond excessively. 

This upregulated responsiveness is associated with changed relative proportions of the main microbiome phyla in the gut, Bacteroidetes and Firmicutes, which might be an indication of dysbiosis. 

What can you do to keep the stressors low?

• Prioritize time to relax, for instance with a book or music
• Do yoga, meditation, and breathwork
• Spend time in nature
• Get enough quality sleep
• Try to destress before meals, to ensure optimal digestion in the rest-and-digest state 
• Consume nutritious whole foods, which do not cause stress responses in the body
• Limit screen time

Takeaway messages

• Stress has negative effects on your health and gut microbiome. It is a key risk factor for many diseases, and can change the composition of your gut microbiome, promote dysbiosis and lead to a leaky gut. 
• Stress can affect your ability to digest food properly, because the rest-and-digest part of your nervous system is downregulated with the presence of stressors.
• Try to limit the stress factors in your life, to improve your overall wellbeing and your gut health. 

Author:  Ingeborg Amble Holtmann