Colonic inflammation from gut endotoxin can cause chronic reactive oxygen species that damage cells and affect brain function, leading to depression.

“I think that the type that you want to interfere with is the colonic inflammation, the kind that's coming from your gut, that's leaking endotoxin, which is released from like dead bacteria and it causes all sorts of damage because it binds to cholesterol. Anyways, I can get into this whole conversation. But it's the bad stuff. The inflammation that's causing that chronic reactive oxygen species which damages DNA, proteins, lipids in your cells which gets into the brain and stops serotonin from being released, so it causes depression and things like that.”