Caffeine vs Lion's Mane
for cognition
Stronger evidence: Caffeine
Stronger effect: Caffeine
Safety: Caffeine carries a minor interaction; Lion's Mane has none recorded.
For cognition, Caffeine has the stronger evidence grade.
Caffeine
grade A high certainty
reliably improves alertness, reaction time, and vigilance
40–200 mg, adults
Lion's Mane
grade C low certainty
early, small studies suggest a modest cognitive effect
~1 g/day, adults
sources: PMID:00000020 · PMID:00000010