Ginkgo vs L-Theanine
for cognition
Stronger evidence: tie
Stronger effect: L-Theanine
Safety: Ginkgo has the more serious interaction profile (serious vs minor).
For cognition, the two are evidence-matched; the difference is in effect and safety.
L-Theanine
grade C moderate certainty
improves attention and reduces distraction, especially combined with caffeine
100–200 mg, adults
sources: PMID:00000034 · PMID:20000107