I didn't have paranoia while on zero-carb but I did get increased anxiety during my raw zero-carb trials(re mental effects:- first couple of weeks felt slightly enhanced mental acuity, then my mind rapidly dulled and I started having memory-issues and lack of concentration etc., before I finally gave up on the diet). I'd had various adrenal-related issues while pre-raw diet, and these came back causing anxiety among other issues. What I found interesting was that certain other conditions I'd had pre-raw diet, such as severely weakened teeth, suddenly started reappearing astonishingly quickly while I was doing zero-carb. Anyway, there has been a claim that going zero-carb puts an extra strain on one's glandular system, so that it might be better to eat a little fruit.
Incidentally, the claim re a slow transition always working certainly did not apply to me, as I, at the time, severely restricted my carb-intake for months before going zero-carb(not because I was planning the trial in advance, I was just on VLC diet(a bit of fruit once a week or fortnight in those days) because I wanted to save money, mostly. Now, my diet is more LC.