21/03/2026
sounds about right. In the early stages of the development of the foetus the brain and gut are one. The gut has the highest amount of nerve endings of any organ apart from the brain.
What seems impossible is unfolding in gut-brain axis research centers where scientists have demonstrated for the first time that specific gut bacterial species — including Lactobacillus reuteri and Bifidobacterium longum — directly produce serotonin precursors and GABA in the intestinal lumen, with these molecules crossing into circulation and measurably altering brain neurotransmitter levels — providing the first direct mechanistic evidence that gut dysbiosis causes depression through neurotransmitter depletion, not merely correlates with it.
The study transplanted microbiomes from depressed human donors into germ-free mice — the animals developed identical depression-like behavioral signatures within 14 days, with their brain serotonin levels dropping by 40% compared to controls receiving healthy donor microbiomes. Reversing the dysbiosis with targeted probiotic restoration eliminated depressive behavior within 7 days. This is not a correlation. The bacteria are the cause. Every antidepressant prescribed while the gut microbiome remains broken is addressing the symptom while ignoring the factory that makes the molecule the symptom requires.