Probiotics vs N-Acetylcysteine

for mood

Stronger evidence: tie

Stronger effect: Probiotics

Safety: No notable interactions recorded for either.

For mood, the two are evidence-matched; the difference is in effect and safety.

Probiotics

grade C low certainty

small effects on mood/anxiety in some "psychobiotic" trials; strain-specific, heterogeneous

strain-dependent, adults

N-Acetylcysteine

grade C low certainty

preliminary evidence as an adjunct in some psychiatric conditions; not established as a standalone

1200–2400 mg/day, adults
sources: PMID:42221774 · PMID:10000012