L-Theanine vs Magnesium

for stress

Stronger evidence: tie

Stronger effect: Magnesium

Safety: Both carry up to minor interactions — check your context.

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

L-Theanine

grade C low certainty

small calming effect; often paired with caffeine to smooth its edge

100–200 mg

Magnesium

grade C low certainty

may modestly reduce subjective anxiety/stress, esp. in deficiency

200–400 mg, adults
sources: PMID:00000022 · PMID:20000101