Lion's Mane vs L-Theanine
for cognition
Stronger evidence: tie
Stronger effect: L-Theanine
Safety: L-Theanine carries a minor interaction; Lion's Mane has none recorded.
For cognition, the two are evidence-matched; the difference is in effect and safety.
Lion's Mane
grade C low certainty
early, small studies suggest a modest cognitive effect
~1 g/day, adults
L-Theanine
grade C moderate certainty
improves attention and reduces distraction, especially combined with caffeine
100–200 mg, adults
sources: PMID:00000010 · PMID:20000107