What the science says
For 743 substances we searched PubMed for meta-analyses, systematic reviews and randomized controlled trials in humans. The grade shows how deep the research base is; each substance page shows what the reviews actually concluded.
3+ meta-analyses or systematic reviews and 10+ randomized controlled trials in humans.
At least one meta-analysis, or 5+ randomized controlled trials.
1–4 randomized controlled trials, no meta-analysis yet.
No randomized controlled trials in humans found on PubMed.
Users ahead of science
Popular and well-rated by users, but little clinical research so far.
Science ahead of users
Heavily studied, but users report modest results.
Grade C: limited research
| Substance | Grade | Meta-analyses | RCTs | User score |
|---|---|---|---|---|
| Agmatine SulfateSupplement | C | 0 | 1 | 61 |
| Magnesium GlycinateSupplement | C | 0 | 4 | 60 |
| Magnesium L-ThreonateSupplement | C | 0 | 3 | 56 |
| GHK-CuPeptide | C | 0 | 1 | 55 |
| PT-141Peptide | C | 0 | 4 | 55 |
| SemaxPeptide | C | 0 | 1 | 54 |
| Zinc PicolinateSupplement | C | 0 | 4 | 54 |
| SelankPeptide | C | 0 | 2 | 52 |
| DynamineSupplement | C | 0 | 2 | 51 |
| MOTS-CPeptide | C | 0 | 4 | 50 |
| PRL-8-53Supplement | C | 0 | 1 | 50 |
| TB-500Peptide | C | 0 | 3 | 50 |
| SS-31Peptide | C | 0 | 3 | 49 |
| ZembrinSupplement | C | 0 | 3 | 44 |
| CentrophenoxineSupplement | C | 0 | 1 | 42 |
| DlpaSupplement | C | 0 | 4 | 41 |
| SulbutiamineSupplement | C | 0 | 4 | 41 |
| AmbienMedication | C | 0 | 4 | 40 |
| CBD IsolateSupplement | C | 0 | 4 | 39 |
| Magnesium ChelateSupplement | C | 0 | 3 | 37 |
| Melanotan 1Peptide | C | 0 | 1 | 37 |
| B Vitamin ComplexSupplement | C | 0 | 4 | 33 |
| NaltSupplement | C | 0 | 1 | 32 |
| Betaine HclSupplement | C | 0 | 3 | 31 |
| PicamilonSupplement | C | 0 | 3 | 31 |
| Pine PollenSupplement | C | 0 | 1 | 31 |
| PramiracetamSupplement | C | 0 | 3 | 31 |
| Zinc GlycinateSupplement | C | 0 | 2 | 31 |
| Vitamin K2 MK7Supplement | C | 0 | 1 | 29 |
| GlynacSupplement | C | 0 | 1 | 28 |
| GuayusaSubstance | C | 0 | 2 | 28 |
| Psilocybin MicrodosingSubstance | C | 0 | 2 | 27 |
| Creatine HclSupplement | C | 0 | 1 | 26 |
| DihydroberberineSupplement | C | 0 | 3 | 26 |
| N-Acetyl TyrosineSupplement | C | 0 | 1 | 26 |
| TrimethylglycineSupplement | C | 0 | 4 | 26 |
| Decaf CoffeeSubstance | C | 0 | 2 | 25 |
| Liposomal GlutathioneSupplement | C | 0 | 2 | 25 |
| N-Acetyl L-TyrosineSupplement | C | 0 | 4 | 25 |
| ReloraSupplement | C | 0 | 1 | 25 |
| TAK-653Substance | C | 0 | 3 | 25 |
| Zinc CarnosineSupplement | C | 0 | 4 | 25 |
| BioperineSupplement | C | 0 | 3 | 24 |
| ThymalinPeptide | C | 0 | 1 | 21 |
| Pumpkin SeedsSupplement | C | 0 | 2 | 19 |
| CiticholineSupplement | C | 0 | 1 | 18 |
| IpamorelinPeptide | C | 0 | 2 | 18 |
| CJC-1295Peptide | C | 0 | 1 | 16 |
| 2-FmaSubstance | C | 0 | 4 | 12 |
| L-TaurineSupplement | C | 0 | 2 | 11 |
| ThymulinPeptide | C | 0 | 4 | 11 |
Counts come from PubMed searches on the substance name in titles and abstracts; trial counts are limited to human studies. A grade reflects how much research exists, not whether the results were positive. Method details