Every ingredient, graded.

Mechanism, the state of the evidence, effective dose, and safety — for the ingredients that show up in cognitive formulas. Grades are our editorial reading of the literature, and we update them as the research moves.

The corpus99 ingredients · graded A+ to C
A+18A26B+26B23C+6

Last reviewed · June 2026 · What the grades mean →

99 ingredients

Educational information, not medical advice. Evidence grades reflect KÖGN’s assessment of published research and are not health claims. Speak to a qualified clinician before changing what you take.

About the Dictionary.

How many nootropic ingredients does KÖGN grade?
KÖGN Health grades 99 nootropic ingredients on a single evidence scale from A+ to C. Each entry covers what the ingredient is, how it works, and the state of the published evidence, with dose and safety notes where the research supports them.
Which nootropics have the strongest evidence?
18 of the 99 ingredients carry KÖGN's A+ grade, meaning strong and consistent human evidence. Caffeine, L-theanine and Bacopa monnieri are among them. Grades are KÖGN's editorial assessment of the literature, updated as the research moves. What each grade means
Are nootropics safe?
Most widely used nootropic ingredients are well tolerated at their studied doses, but safety differs by compound, dose, and the medication you already take. Each Dictionary entry carries safety notes where the evidence supports them. Speak to a qualified clinician before changing what you take.
How often are the grades updated?
Grades are revisited as new research is published; the corpus was last reviewed in June 2026. A grade is an editorial reading of the evidence, not a health claim.