Caffeine and Rhodiola Rosea
Each entry’s own grades, side by side. A grade says how strong the evidence is for one outcome — it does not rank one entry over the other.
Compound or practice
Caffeine
The most-used and best-evidenced cognitive and physical stimulant on earth — precise dosing and a hard afternoon cutoff are the whole skill.
Grade A4 graded outcomesrevised Jul 10, 2026
A structured monograph in Prometheus's bundled library. Its grades are the monograph's own reading of the evidence, not a peer-reviewed review.
Compound or practice
Rhodiola Rosea
A stimulating adaptogen with the best fatigue evidence among the herbal 'stress' supplements — daytime energy without ashwagandha's flatness.
Grade B3 graded outcomesrevised Jul 10, 2026
A structured monograph in Prometheus's bundled library. Its grades are the monograph's own reading of the evidence, not a peer-reviewed review.
Graded in both
Outcomes are matched by name. Two entries can describe the same outcome in different words, so one listed further down may still be graded in the other.
No outcome has the same name in both entries. They may still overlap under different wording — read the two lists below.
Graded only in Caffeine
- Alertness / reaction time Moderate effectEvidence grade A
- Endurance performance Moderate effectEvidence grade A
- Strength / power Small effectEvidence grade B
- Sleep (afternoon dosing) Moderate effectEvidence grade A
Graded only in Rhodiola Rosea
- Fatigue / burnout Moderate effectEvidence grade B
- Stress symptoms Small effectEvidence grade B
- Cognition under fatigue Small effectEvidence grade C
Conditions
Only in Caffeine
None.
Only in Rhodiola Rosea
- Burnout / chronic fatigue May improveEvidence grade C
What each entry says about the other
- Caffeine’s entry · Caution: Both activating — stack low-dose.
- Caffeine’s entry · Watch with: Both activating — stack low-dose.
- Rhodiola Rosea’s entry · Caution: Both activating — stack low-dose or trade calm focus for edge.
- Rhodiola Rosea’s entry · Watch with: Both activating — stack low-dose or trade calm focus for edge.
Both columns are read from the entries as they stand in this library. A comparison is not advice to take either one, and it is no substitute for a clinician who knows the person.