Within the last 10 or 20 years, the conversation around gut health has greatly changed. The recognition that the gut microbiome, the trillions of bacteria and other microorganisms in your gut, is a key influencer of health and disease in the body has revolutionized the way we think about our digestive health. There is now an increased incentive to strive to maintain ‘good gut health’, which involves having a diverse, balanced gut microbiome and limited digestive symptoms (1).  

Living in urban environments has been associated with a reduction in gut microbiome diversity, yet the exact reason for this is still unclear (2). Potential causes for loss of gut microbial diversity include changes to modern diets, lifestyle factors, increased cleanliness in homes, and increased antibiotic usage. A wide range of diseases are also associated with altered microbiome composition, including alcoholic and non-alcoholic fatty liver disease (3), cardiometabolic diseases (4), and cancer (5,6).  

Microbiome composition is also important in many gastrointestinal diseases, such as inflammatory bowel disease (IBD) (7,8), and more people than ever now suffer from gastrointestinal issues; approximately 40% of the world’s population (9). A focus on gut health has therefore never been more important, but why has it taken so long for the full importance of gut health to be recognized? Here we discuss how our understanding of gut health has evolved over the years, and what that means for us now and in the future.  

The Origins of Gut Health Research 

In the 17th century, the observation of feces under a microscope led to the identification of moving cells that were termed ‘animalcules’, but we now know as bacteria (10). This was the first time that the link between bacteria and the gut was recognized. However, it wasn’t until almost two centuries later that these findings were pursued in the 1853 book ‘A Flora and Fauna within Living Animals’, which is widely considered to be the origin of microbiome research (11). This work inspired further research by Louis Pasteur, who developed the germ theory of disease and proposed that non-pathogenic microbes had a key role in human health.  

Microbes beneficial to our gut health have been used in many different treatments over the centuries. For instance, fecal microbiota transplants (FMTs), which involve transferring fecal bacteria from one patient to another to treat gastrointestinal disease, were first described over 1700 years ago as part of traditional Chinese medicine (12). It wasn’t until 1958 that FMTs were used in modern clinics to successfully treat Clostridium Difficile infections (11). Other bacterial treatments were also used in the early 20th century, such as the discovery of an E. Coli strain during World War I that could be encapsulated inside gelatine pills to treat dysentery (an intestinal infection that causes diarrhea with blood or mucus) (2).  

Throughout the 20th century, the topic of gastrointestinal health was considered quite taboo, usually only to be discussed with doctors and dieticians. Even now, elements of this stigma remain, with research by Guts UK revealing that 58% of people are embarrassed to talk about their digestive symptoms, and 51% of people delay seeking advice for these symptoms for more than 6 months (13). However, the conversation is widening around these topics with the advancing understanding of the importance of gut health. In fact, this importance has been recognized after advancements in technology towards the end of the 20th century allowed improved analysis and identification of the microbes making up the microbiome.

The Re-discovery of the Microbiome  

In 1998, it was determined that each individual has a unique microbiome (14). These and other related research developments were seen as a ‘rediscovery’ of the microbiome, as they offered huge new insights into understanding the microbiome after years of little progress.  

In 2007, The Human Microbiome Project was launched. After the first phase focused on identifying and characterizing the human microbiome was completed, a second phase attempted to reveal the impact of the human microbiome on various diseases. There has been an exponential increase in our understanding of the functions of the microbiome since its rediscovery, with some key discoveries opening vast new areas of research. For instance,  connections between the gut microbiome and the brain are currently being particularly highlighted, with new studies revealing that mental health conditions such as anxiety and depression are strongly associated with dysregulation of the gut microbiome (15). 

Understanding Your Microbiome 

The newfound understanding of the importance of the microbiome has revealed insights into lifestyle changes, dietary changes, and treatments that can help to improve our overall health through our gut. However, given that everyone has a unique gut microbiome, none of this understanding is of any use if we can’t understand and monitor our personal gut health. This is where breath testing comes in.  

Hydrogen perhaps remains the most well-established breath biomarker of gastrointestinal disease (16). Hydrogen gas is normally produced by certain bacteria in the large intestine, and some gut microbes can also produce methane. These gases are then absorbed into the blood where it can travel to the lungs to be excreted in breath, allowing for their detection.  

Both hydrogen and methane can be produced by a healthy gut microbiome, yet when the gut microbiome becomes dysregulated, the levels of these gases can be increased leading to unpleasant symptoms such as bloating and abdominal discomfort, as in small bacterial intestinal overgrowth (SIBO). The increase in these gases can be detected using hydrogen methane breath tests developed by OMED to infer whether patients have SIBO.  

What’s next for gut health?  

Whilst leaps and bounds of progress have been made into understanding the microbiome since its ‘rediscovery’, more research needs to be done to gain a full understanding of its interactions within our bodies. The accessibility of the internet and social media allows more resources than ever to be available to people who would like to improve their gut health, but monitoring our personal gut health can be used to ensure that we are taking the correct actions to improve it.  

Our OMED Health Breath Analyzer is a portable, handheld device used to monitor hydrogen and methane levels in the breath, with the data displayed in the companion app. The device allows easy monitoring of symptoms to help maintain good gut health by identifying causes of gastrointestinal symptoms, such as different food intolerances or SIBO. This can inform lifestyle or dietary changes that can be made to help improve symptoms, creating a balanced and diverse microbiome.  

References

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