I have same anecdotal evidence about my mood. I had some tooth infections and took some strong horse dose antibiotics couple times in my life and my mood and “adhd” symptoms got better.
A lot of people (me included) report this when they induce ketosis after eliminating carbs and sugar. It would seem reducing carbs and sugars would drastically change the biotic makeup of one's gut, so this is all seeming to be tied to ones gut... microbiota is very interesting.
That does not surprise me at all.
For depression there is the chronic inflammation hypothesis which states that depression is caused by subacute inflammation in the brain. Some antibiotics work as antiinflammatory agents. Although a recent study did not show significant evidence for the treatment of chronic depression with antibiotics.
Then there is something along the lines of underexpressed BDNF genes which get more expressed by butyrate which in turn is produced by gut bacteria.
And there have been some case studies for treatment resistant depression where they did a stool transplant which improved the symptoms considerably.
Anecdotally, I‘ve experienced these benefits after ca 9 months of strictly no sugar (not even fruit). But just a couple weeks of eTRF (stopping to eat at 3PM) gave the same results (normal IF did nothing of the kind for me).
