Supplement Evidence Database
Search and filter popular supplements. Each claimed use is graded from A (strong evidence) to D (no good evidence), with typical onset times and safety warnings.
34 of 34 supplements
| Supplement | Use and evidence grade | Typical onset |
|---|---|---|
| Creatine Performance | AStrength and power with training ALean mass with training CMemory and cognition | 7 days – 4 weeks |
| Folic acid Vitamin | APreventing neural tube defects (before pregnancy) | 4 weeks – 13 weeks |
| Iron Mineral | AIron-deficiency anemia DFatigue without deficiency | 2 weeks – 13 weeks |
| Lutein & zeaxanthin (AREDS2) Eye health | ASlowing intermediate AMD (AREDS2 formula) | 6 months – 12 months |
| Magnesium Mineral | ACorrecting low magnesium AConstipation (citrate, oxide) BBlood pressure CSleep quality | 2 weeks – 8 weeks |
| Omega-3 (EPA/DHA) Essential fat | ALowering high triglycerides BRheumatoid arthritis symptoms CHeart disease prevention (general population) | 4 weeks – 12 weeks |
| Psyllium fiber Fiber | AConstipation ALowering LDL cholesterol | 12 h – 3 days |
| Vitamin B12 Vitamin | ATreating deficiency DEnergy without deficiency | 2 weeks – 8 weeks |
| Vitamin D3 Vitamin | ACorrecting deficiency BBone health with calcium (older adults) CRespiratory infections DPreventing heart disease or cancer | 8 weeks – 13 weeks |
| Zinc Mineral | ACorrecting deficiency BShorter colds (lozenges) CPreventing colds | 1 day – 7 days |
| Ashwagandha Herb | BPerceived stress CSleep quality CAnxiety | 6 weeks – 8 weeks |
| Berberine Plant compound | BBlood sugar in type 2 diabetes CWeight loss | 4 weeks – 13 weeks |
| Calcium Mineral | BBone health with vitamin D (older adults) | 6 months – 12 months |
| CoQ10 Antioxidant | BHeart failure (add-on) CStatin muscle symptoms CMigraine prevention | 4 weeks – 12 weeks |
| L-Theanine Amino acid | BShort-term stress BFocus with caffeine CSleep quality | 30 min – 60 min |
| Melatonin Hormone | BJet lag BFalling asleep faster | 30 min – 60 min |
| NMN / NR Longevity | BRaising blood NAD CSlowing aging in humans | 2 weeks – 9 weeks |
| Potassium Mineral | BBlood pressure (low-potassium diets) ⚠ Dangerous with some blood pressure medicines and kidney disease. | 4 weeks – 8 weeks |
| Probiotics Gut health | BAntibiotic-associated diarrhea CIBS symptoms DGeneral health in healthy adults | 3 days – 4 weeks |
| Red yeast rice Cholesterol | BLowering LDL cholesterol ⚠ Can contain monacolin K, chemically identical to the statin lovastatin. Don't combine with statins. | 4 weeks – 12 weeks |
| St. John's wort Herb | BMild to moderate depression ⚠ Interacts with many medicines, including birth control, antidepressants and blood thinners. | 4 weeks – 6 weeks |
| Vitamin C Vitamin | BShorter colds (regular use) DPreventing colds | 7 days – 4 weeks |
| Collagen peptides Protein | CSkin hydration and elasticity CJoint pain | 8 weeks – 12 weeks |
| Echinacea Herb | CPreventing or treating colds | 1 day – 7 days |
| Elderberry Herb | CShorter colds or flu | 1 day – 5 days |
| Glucosamine Joint | CKnee osteoarthritis pain | 4 weeks – 12 weeks |
| Rhodiola Herb | CMental fatigue | 3 days – 4 weeks |
| Turmeric / curcumin Herb | CKnee osteoarthritis pain | 4 weeks – 12 weeks |
| Valerian Herb | CSleep quality | 2 weeks – 4 weeks |
| Vitamin K2 Vitamin | CBone density CArterial calcification | 13 weeks – 12 months |
| Biotin Vitamin | DHair growth without deficiency ⚠ High doses can interfere with some lab tests, including thyroid and heart tests. Tell your doctor before blood work. | 8 weeks – 4 months |
| Garcinia cambogia Weight loss | DWeight loss | 4 weeks – 12 weeks |
| Ginkgo Herb | DPreventing memory decline or dementia | 4 weeks – 12 weeks |
| Green tea extract Herb | DWeight loss ⚠ Concentrated extracts have been linked to rare liver injury, especially on an empty stomach. | 4 weeks – 12 weeks |
Sources
Free tool for education only. It doesn't replace advice from your doctor or pharmacist.