Researchers are not talking about whole bacteria passing through the gut in leaky gut, that would be sepsis. They are talking about endotoxins and bacterial DNA passing through.
This can provoke an immune response, as if they were whole bacteria. Whole bacteria are not even necessary for full blown sepsis, a high level of LPS will cause sepsis.
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Leaky gut has been found in Diabetes, MS, Parkinson's, fatty liver disease, cirrhosis, Chronic kidney disease, and probably many more diseases.
What is more likely, that all of these very different pathologies are somehow causing a leaky gut OR, a leaky gut is causing inflammation that plays a significant, if not decisive role in the pathology of these diseases?
I am convinced it is the latter and there are countless studies over many years, by thousands of researchers, that leaky gut and LPS translocation is not only real but very common.
Jim