Dr. Amy Nett: There are a number of different ways that dysbiosis potentially contributes to HPA axis dysfunction. One of the reasons is that dysbiosis is just a form of stress. Whenever we talk about HPA axis dysfunction, essentially what we’re talking about is too much stress. The body is seeing a lot of different sources of stress. Those are going to be internal and external. Chronic infection is interpreted by the body as a source of stress, so it’s an internal form of stress.
The other thing, though, is we know that dysbiosis also increases inflammation. It’s associated with intestinal permeability, and those are going to contribute to dysregulation of the HPA axis.
We also know that there’s a very strong brain and gut connection. You can think of the gut-brain axis, and the HPA axis dysregulation is primarily dysregulation coming from the brain. It’s really looking at the hypothalamus and the pituitary, which is why we try to avoid saying “adrenal fatigue syndrome,” because it’s not directly related to the adrenals. It’s much more tied into the hypothalamus and the pituitary. Just understanding that there are several different mechanisms involved in the gut-brain axis, understanding then the gut is going to contribute to what the hypothalamus is perceiving, that’s going to contribute to HPA axis dysregulation. There are several different mechanisms involved in that connection.