Stress
The stress response is the HPA axis doing its job: a cortisol rhythm that mobilizes you in the morning and stands down at night. Sustained load keeps the axis switched on — and that is what stress-focused supplements are actually tested against: perceived-stress scales and cortisol measured over weeks, not moments of instant calm.
Two root extracts carry most of the evidence here, ashwagandha and rhodiola, with theanine as a gentler, better-tolerated third option. All of it tops out at grade B: real trials, real caveats about how few research groups ran them. Interaction lists matter more in this category than any other — check them before choosing, especially if you take an SSRI.
Ranked by evidence
- Ashwagandha 300–600 mg standardized root extract daily for 6–12 weeks; check the interaction list first
- Rhodiola rosea 200–600 mg extract in the morning; take before food, avoid late-day doses
- L-theanine 200 mg once or twice daily
- Magnesium glycinate 200–400 mg in the evening; stress evidence is weak, sleep support is the realistic path
Grades are per goal–ingredient pairing, hand-assigned from the evidence records linked on each monograph. Ingredients without a link have a monograph on the way.
What does not work (yet)
- Whole-root ashwagandha powder. Traditional doses are much higher and less consistent than the standardized extracts the trials used — hard to map to any evidence.
- Magnesium as a primary stress tool. A systematic review found only suggestive changes and rated trial quality poor. Its realistic contribution is through sleep.
The list above is the general case. Your medications, current stack, budget, and other goals change it — sometimes a lot.