So, what happened?

• A high fermentable diet (HFD) resulted in increased levels of short-chain fatty acids (beneficial for gut and overall general health);
• HFD resulted in increased gas production in the colon; even more, gas was produced in the high histamine mice only;
• HFD altered transit and intestinal permeability in the high histamine mice only;
• HFD altered levels of visceral pain (pain associated with the abdominal area due to the activation of nerve fibers) in the high histamine mice only;
• Mast cells (contain lots of histamine) co-localized with intestinal nerve fibers in the high histamine mice only;
• HFD increased the number of intestinal nerve fibers in the high histamine mice only;
• HFD stimulated the histamine receptor (increased histamine = increased histamine receptor) in the high histamine mice only;
• HFD resulted in low grade inflammation, which was linked to bacterial production of histamine and not necessarily through inflammatory mediators.

That was a lot, what does it all mean?

High fermentable foods (e.g. FODMAPs) can lead to huge levels of gas production in the colon. The levels of gas production appear to correlate with increased histamine levels. Symptoms are driven by diets high in fermentable foods, including abdominal pain, visceral hypersensitivity and intestinal permeability – again this seems to be associated with increased histamine levels. These changes appear to be driven by the gut microbes and their level of histamine production. How your diet (HFD vs LFD) interacts with your microbial mix, can have a huge influence on symptom generation and can greatly impact your metabolome. The metabolome is the collection of the small molecules produced during metabolism and is a very good indicator of what is actually happening within the intestinal environment.

The fact that IBS is such a heterogeneous disorder, means that multiple factors are at play, and these can vary depending on the patient. Personalizing the management of your symptoms can be challenging but is very important, as many available treatments are not satisfactory, resulting in symptom relapse for many. Focusing on your diet is a great place to start. Speak with a registered dietitian or health care provider to let them guide you along the way.