More on the subject of people reacting differently to the same bacteria…
A study[i] out of Sweden shows that the intestinal barrier in the colon of people with irritable bowel syndrome allows more bacteria to pass freely through the intestinal mucosa causing an immune reaction.
The researchers took tissue samples from the large intestines of 37 women with IBS and compared them to normal controls, after introducing both the a Salmonella pathogen (infection with this is a risk factor for the development of IBS) and also, a type of E. coli found commonly in intestines. Both bacteria passed through the intestinal mucosa of the IBS patients twice as rapidly as the tissue from the healthy controls.
More than that, they also found that the mast cells (a part of our innate immune system) of those with IBS are more active. Mast cells, when active, release a host of pro-inflammatory chemicals including histamines, and are a major factor in allergic responses.
While it is as yet unknown if this in vitro effect happens in vivo, the lead researcher states that, “What we can say, however, is that there is something that makes one layer of the intestinal mucosa of patients with IBS more sensitive to bacteria than healthy subjects.”
Why, of course, is the question. Since people with IBS are also more likely to have issues with anxiety and depression[ii], both of which are also associated with alterations in the bacterial microbiome and inflammation…you do have to wonder at the root of this all: depleted biomes? Higher levels of stress in our modern society? Altered immunity?…or maybe, all of the above?!