Supplement Evidence Report
We catalogued 816 peer-reviewed studies across 557 compounds and 200+ herbs. Here's what the evidence actually looks like when you grade every study on the same scale.
Evidence Distribution
Evidence by Category
| Category | Strongest Evidence | Weakest Evidence | Key Gap |
|---|---|---|---|
| Adaptogens | Ashwagandha (stress) | Most adaptogens | Only ashwagandha has replicated RCTs |
| Cognitive | Caffeine, creatine | Lion's Mane, Bacopa | Plausible mechanisms, few large trials |
| Metabolic | Berberine (glucose) | Most fat burners | Berberine is the standout |
| Sleep | Melatonin, magnesium | Valerian, passionflower | Herbal sleep aids are thin |
| Mood | St. John's Wort | Saffron, NAC | St. John's Wort is well-studied; alternatives need data |
| Immune | Vitamin D, zinc | Elderberry, echinacea | Micronutrients > botanicals |
| Performance | Creatine, caffeine | Cordyceps, ashwagandha | Sports supplements strongest overall |
What This Means
Most supplements are under-studied
60% have limited, preliminary, or traditional-use evidence only. This doesn't mean they don't work — it means we don't know.
The strong-evidence list is short
Only ~15% of supplements have strong clinical evidence. Start with those if you want certainty.
Quality matters as much as evidence
A supplement with Grade A evidence is useless if the product in the bottle doesn't match the product in the study. Verify quality independently.
This data is updated annually. Full methodology at /info/methodology. Read the full report: State of Supplement Evidence 2026
Learning context
How this concept connects to supplement decisions
Evidence distribution and grading summary across The Hippie Scientist supplement and herb research library. Learning pages explain the reasoning layer behind the herb and compound library. They are designed to make mechanisms, evidence quality, safety tradeoffs, and product claims easier to interpret.
Use Supplement Evidence Report to build better questions before choosing a supplement: what outcome is being targeted, what mechanism is claimed, what human evidence exists, what dose was studied, and what risks could change the answer for a specific person?
Mechanistic plausibility is useful, but it should be weighed against trial design, safety history, product quality, and the possibility that a simpler intervention may be more appropriate.