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ProtocolEngine provides general health information based on published research. This is not medical advice. Consult a healthcare professional before starting any supplement or health protocol.

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Supplement Tier List

Every supplement ranked by the strength of its research. Click any supplement for full details, studies, and dosage.

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S

Foundational supplements backed by decades of human research and consistent results across populations. Well-understood, strong safety profiles.

6 items
Probiotics
typical effect size 67 of 100
Omega-3 (EPA/DHA)
typical effect size 60 of 100
Curcumin
typical effect size 76 of 100
Fiber
typical effect size 61 of 100
Saffron
no effect-size data yet
Vitamin D3
typical effect size 61 of 100
A

Strong evidence from multiple high-quality human studies with meaningful, measurable benefits. Well-documented for specific outcomes.

32 items
Calcium
typical effect size 59 of 100
Collagen Peptides
typical effect size 61 of 100
Vitamin D
typical effect size 62 of 100
Folate
typical effect size 67 of 100
NAC (N-Acetyl Cysteine)
typical effect size 70 of 100
Melatonin
typical effect size 53 of 100
Magnesium
typical effect size 33 of 100
Hyaluronic Acid
typical effect size 68 of 100
Caffeine
typical effect size 58 of 100
Vitamin K
typical effect size 83 of 100
Vitamin E
typical effect size 70 of 100
Zinc
typical effect size 68 of 100
Iron
no effect-size data yet
Vitamin C
no effect-size data yet
Whey Protein
no effect-size data yet
Choline
typical effect size 66 of 100
Magnesium Glycinate
typical effect size 66 of 100
Lutein
typical effect size 65 of 100
Vitamin K2 (MK-7)
typical effect size 57 of 100
Zeaxanthin
typical effect size 61 of 100
Lycopene
typical effect size 66 of 100
Palmitoylethanolamide (PEA)
no effect-size data yet
Lavender
no effect-size data yet
Vitamin B12
no effect-size data yet
Creatine
typical effect size 53 of 100
Glutathione
typical effect size 66 of 100
CoQ10 (Ubiquinol)
typical effect size 66 of 100
Inositol (Myo-Inositol)
typical effect size 62 of 100
Casein Protein
typical effect size 59 of 100
Potassium
typical effect size 59 of 100
Berberine
typical effect size 61 of 100
Spirulina
typical effect size 66 of 100
B

Promising research with positive human studies, but often small, short-term, or limited to specific groups. Worth considering with realistic expectations.

68 items
Vitamin B6
no effect-size data yet
Chromium
no effect-size data yet
Vitamin A
typical effect size 66 of 100
Selenium
typical effect size 61 of 100
Sodium Bicarbonate
no effect-size data yet
BCAA
typical effect size 83 of 100
L-Carnitine
no effect-size data yet
Resveratrol
typical effect size 60 of 100
Quercetin
typical effect size 33 of 100
Copper
typical effect size 100 of 100
Anthocyanins
typical effect size 66 of 100
Milk Thistle
typical effect size 33 of 100
Ashwagandha (KSM-66)
no effect-size data yet
Methylene Blue (low dose)
no effect-size data yet
L-Glutamine
no effect-size data yet
Taurine
typical effect size 55 of 100
GABA
no effect-size data yet
Capsaicin
typical effect size 66 of 100
Boswellia
no effect-size data yet
Creatine Monohydrate
typical effect size 64 of 100
L-Tyrosine
typical effect size 100 of 100
Beetroot Juice
no effect-size data yet
Glycine
no effect-size data yet
Black Seed Oil
no effect-size data yet
Beta-Carotene
typical effect size 64 of 100
L-Citrulline
no effect-size data yet
Iodine
no effect-size data yet
Phosphorus
no effect-size data yet
Astaxanthin
no effect-size data yet
Thiamine (Vitamin B1)
no effect-size data yet
Rhodiola Rosea
no effect-size data yet
L-Tryptophan
no effect-size data yet
Niacin (Vitamin B3)
typical effect size 58 of 100
Vitamin D2 (ergocalciferol)
no effect-size data yet
Saw Palmetto
no effect-size data yet
Biotin
no effect-size data yet
Manganese
no effect-size data yet
Beta-Alanine
typical effect size 46 of 100
L-Theanine
typical effect size 66 of 100
Citicoline
no effect-size data yet
Valerian Root
no effect-size data yet
Electrolytes
no effect-size data yet
Soy isoflavones
no effect-size data yet
Piperine
no effect-size data yet
Ergothioneine
no effect-size data yet
Urolithin A
no effect-size data yet
Bacopa Monnieri
no effect-size data yet
Gamma-Linolenic Acid (GLA)
no effect-size data yet
Luteolin
no effect-size data yet
Citrulline Malate
typical effect size 60 of 100
NMN (Nicotinamide Mononucleotide)
typical effect size 100 of 100
Spermidine
no effect-size data yet
Passionflower
no effect-size data yet
Naringenin
no effect-size data yet
Vitamin B Complex
no effect-size data yet
Tart Cherry (Montmorency)
typical effect size 66 of 100
Sulforaphane
no effect-size data yet
Garcinia Cambogia
no effect-size data yet
Vitamin K1 (phylloquinone)
typical effect size 66 of 100
Phosphatidylserine
no effect-size data yet
Nicotinamide Riboside (NR)
no effect-size data yet
Echinacea (Echinacea purpurea)
no effect-size data yet
Citrus Bergamot
no effect-size data yet
Apigenin
no effect-size data yet
Vitex (Chasteberry)
typical effect size 100 of 100
Lion's Mane
no effect-size data yet
Kava
no effect-size data yet
Fisetin
no effect-size data yet
C

Early-stage or mixed evidence. Limited human research, or results that conflict across studies. Approach with healthy skepticism.

23 items
Beta-glucan
typical effect size 66 of 100
Maca
no effect-size data yet
Dihydromyricetin (DHM)
no effect-size data yet
Oleocanthal
no effect-size data yet
Elderberry
typical effect size 66 of 100
Tongkat Ali
no effect-size data yet
Shilajit
no effect-size data yet
Hesperidin
no effect-size data yet
Ellagic acid
typical effect size 66 of 100
MCT Oil
no effect-size data yet
5-HTP
no effect-size data yet
PQQ
no effect-size data yet
Thymol
no effect-size data yet
Alpha-GPC
no effect-size data yet
Dietary nitrates
no effect-size data yet
Sesamin
no effect-size data yet
Boron
no effect-size data yet
Carvacrol
no effect-size data yet
Allicin
no effect-size data yet
Cinnamaldehyde
no effect-size data yet
Magnesium Threonate
no effect-size data yet
Alpha-Ketoglutarate
no effect-size data yet
Nattokinase
no effect-size data yet
D

Developmental. Supported mainly by animal or in-vitro studies. No solid human trials yet, but pre-clinical results are worth watching.

3 items
Epitalon
no effect-size data yet
Centrophenoxine
no effect-size data yet
GHK-Cu (Copper Tripeptide)
no effect-size data yet
E

Insufficient evidence, or human studies showing no benefit (sometimes potential harm). Look elsewhere.

7 items
Rosmarinic acid
no effect-size data yet
Pterostilbene
no effect-size data yet
Ephedra
no effect-size data yet
Avenanthramides
no effect-size data yet
Gingerol
no effect-size data yet
Lithium Orotate
no effect-size data yet
C60 (Fullerene)
no effect-size data yet
How to read this: Supplements are ranked from S (strong human evidence) through A, B, C (decreasing levels of human research), to D (developmental, mostly animal or in-vitro), and E (insufficient or evidence against).