Bridging the brain-body gap: How the ‘thinking’ gut influences mental well-being
Jack Challem, a writer and author of more than 20 books on nutrition, was speaking at the Natural & Organic Products Europe in London.
Here, he spoke about how the latest research was unravelling the complex mechanisms of action probiotics follow to positively influence conditions such as depression and autism.
“The communication pathways occur in a number of ways. Gut bacteria produce ‘feel good’ brain chemicals as well as the existence of direct cell-to-cell communication,” said Challem. “In addition, the lymphatic system could be considered another pathway from the gut to the brain.
The link between gut nutrition and the brain is a good example of a connection between the physiological and psychological.”
Challem was referring to the bidirectional communication between the gut and the brain, known as the gut–brain axis. This relationship forms the basis of the relatively new research field of gastroneuroenterology.
Studies that have resulted have opened up realistic opportunities of developing novel microbial-based strategies for treatment for stress-related psychiatric disorders.
He referred to a study that demonstrated that human intestinal flora regulated the levels of the body's main antioxidant, glutathione.
The research itself has significance in metabolic function. Researchers believe the link could lead to understanding of how bacteria play a role in the processes involved in developing obesity, type 2 diabetes, non-alcoholic fatty liver disease as well as malnutrition.
However, Challem was quick to highlight that one of glutathione’s precursors, N-Acetylcysteine, has been the subject of studies that investigated its use in treating drug addiction and alcoholism.
Known as the enteric nervous system, the gut is made up of neurons lining the walls of the gut, which measures roughly nine metres end to end from the oesophagus to the anus.
More significantly, the gut’s alimentary canal, contains over 100 million neurons, more than in either the spinal cord or the peripheral nervous system.
Challem made reference to the gut as the body’s ‘second brain,’ a term first coined by Michael Gershon, chairman of the Department of Anatomy and Cell Biology at New York–Presbyterian Hospital/Columbia University Medical Center, and author of the 1998 book, ‘The Second Brain.’
In his book, Gershon wrote that the process of breaking down food, absorbing nutrients, and expelling of waste involves physiological processes such as chemical processing, mechanical mixing and rhythmic muscle contractions.
Gershon argued that the gut must have evolved its own reflexes and senses to be able to control gut behaviour independently of the brain.
It thus stands to reason, said Challem that the food and nutrients consumed would have a bearing on an individual’s mood as well as their physical and mental well-being.
A study goes someway to confirming this as researchers discovered that the gut was not only capable of autonomy but also exerted significant power on brain function.
The study found that approximately 90% of the signals passing along the autonomic nervous system come not from the brain but from the gut.
The feel-good factor
Further down the line, the raft of studies that are characterising gastroneuroenterology are almost guaranteed to offer new insight into the workings of the second brain—and its impact on the body and mind.
Therein lies a new challenge. Challem commented that while the research showed great promise, its significance to the consumer would need to be communicated in such a way that better resonated with the target market. He believed a ‘benefits first’ approach might be wise.
“I think it's important to keep the consumer marketing messages short and simple, but it's crucial for companies to educate retailers. The science must be simplified for the average consumer, even if it states only the benefits,” he said.
“After all, the consumer wants to know "How will this help me?" Many people assume the science has been done when they hear a health claim.”