Amino acids

Protein building blocks and derivatives used for performance and recovery.

Browse published ingredients in this bucket. Scores are model outputs for orientation - read each page for mechanisms, dosing notes, and who should avoid. How we score.

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Overall score Evidence Safety Hype gap (low first)

Where readers often start

In Amino acids, these published hubs are a common entry point (by overall score for this sort order): Creatine · Whey protein · Beta-alanine · Leucine · Casein protein.

Comparisons inside this category

Side-by-side pages where both ingredients appear in Amino acids.

Beta-alanine vs Creatine
Collagen peptides vs Whey protein
Essential amino acids (EAAs) vs Whey protein

Creatine
90
Creatine monohydrate has extensive human evidence for strength/power outputs and is generally well tolerated at common doses.
Strong supportEv 93Hype 28
Whey protein
84
Whey is a practical, leucine-rich protein for muscle protein synthesis when total daily protein and training are in place.
Strong supportEv 86Hype 42
Beta-alanine
83
Beta-alanine is one of the better-supported performance ingredients - for specific event durations, not everything athletic.
Strong supportEv 85Hype 38
Leucine
78
Leucine is real biochemistry; it is not a license to ignore overall protein or progressive overload.
Strong supportEv 80Hype 48
Casein protein
74
Casein protein is commonly associated with: slow-release protein marketing. Our registry tags evidence as high; this hub translates that into an ingredient-level verdict with safety and hype context - not individualized recommendations.
PromisingEv 78Hype 44
Essential amino acids (EAAs)
74
EAAs are scientifically coherent for muscle protein signaling, but often redundant if dietary protein is already high.
PromisingEv 76Hype 52
L-citrulline
74
Citrulline has reasonable mechanistic and trial support for endurance-oriented outcomes in some populations; effect sizes vary.
PromisingEv 72Hype 48
Taurine
70
Taurine is generally safe and biologically interesting; human performance claims are plausible but not rock-solid across endpoints.
PromisingEv 66Hype 48
Betaine anhydrous
68
Betaine can be useful in specific training studies; it is not a guaranteed PR pill for everyone.
PromisingEv 65Hype 52
Glycine
68
Glycine has intriguing sleep-latency trial data for some people; evidence base is smaller than melatonin for circadian issues.
PromisingEv 62Hype 48
BCAAs (leucine/isoleucine/valine)
66
BCAAs (leucine/isoleucine/valine) is commonly associated with: muscle preservation marketing; fatigue in liver disease (specialized contexts). Our registry tags evidence as medium; this hub translates that into an ingredient-level verdict with safety and hype context - not individualized recommendations.
Mixed evidenceEv 62Hype 52
EAAs (essential amino acid blends)
66
EAAs (essential amino acid blends) is commonly associated with: muscle protein synthesis marketing; fasting training stacks. Our registry tags evidence as medium; this hub translates that into an ingredient-level verdict with safety and hype context - not individualized recommendations.
Mixed evidenceEv 62Hype 52
L-Leucine
66
L-Leucine is commonly associated with: mps signaling marketing. Our registry tags evidence as medium; this hub translates that into an ingredient-level verdict with safety and hype context - not individualized recommendations.
Mixed evidenceEv 62Hype 52
Pea protein isolate
66
Pea protein isolate is commonly associated with: vegan protein completeness with blends. Our registry tags evidence as medium; this hub translates that into an ingredient-level verdict with safety and hype context - not individualized recommendations.
Mixed evidenceEv 62Hype 52
Rice protein isolate
66
Rice protein isolate is commonly associated with: hypoallergenic vegan protein. Our registry tags evidence as medium; this hub translates that into an ingredient-level verdict with safety and hype context - not individualized recommendations.
Mixed evidenceEv 62Hype 52
L-Lysine
64
Essential amino acid; cold sore trials show modest benefit; muscle claims are weaker. We summarize evidence, safety, and hype as editorial context-not medical advice.
PromisingEv 60Hype 42
L-tyrosine
64
Helpful in narrow cognitive stress models; less proven as daily anxiolytic.
PromisingEv 60Hype 52
L-glutamine
62
Glutamine matters in catabolic illness; healthy gut bloating often has many non-glutamine causes.
Mixed evidenceEv 58Hype 50
Collagen peptides
61
Collagen is not magic; selected trials suggest possible skin and joint symptom benefits, often industry-funded and modest in effect size.
Mixed evidenceEv 58Hype 72
L-carnitine
60
Carnitine is not a stimulant fat burner for replete omnivores.
Mixed evidenceEv 58Hype 50
HMB (β-hydroxy β-methylbutyrate)
58
HMB shows signals in some populations for lean mass retention, but trained lifters often see null results in trials.
Mixed evidenceEv 55Hype 60
L-arginine
58
Arginine is real physiology; pills do not always recreate infusion physiology.
Mixed evidenceEv 54Hype 58
L-tryptophan
58
Tryptophan is not a free pass to stack with antidepressants.
Mixed evidenceEv 54Hype 48
Acetyl-L-carnitine
56
ALCAR crosses marketing lines between mitochondria cosplay and real neuropathy adjuvants.
Mixed evidenceEv 52Hype 54
Carnosine
56
Dipeptide for aging and exercise; eye and cognitive interest; human data are mixed. We summarize evidence, safety, and hype as editorial context-not medical advice.
Mixed evidenceEv 52Hype 54
Collagen peptides (hydrolyzed)
56
Collagen peptides (hydrolyzed) is commonly associated with: skin/joint marketing. Our registry tags evidence as low; this hub translates that into an ingredient-level verdict with safety and hype context - not individualized recommendations.
Insufficient evidenceEv 48Hype 64
Hemp protein
56
Hemp protein is commonly associated with: vegan protein + fiber. Our registry tags evidence as low; this hub translates that into an ingredient-level verdict with safety and hype context - not individualized recommendations.
Insufficient evidenceEv 48Hype 64
L-Proline
56
L-Proline is commonly associated with: collagen-adjacent stacks. Our registry tags evidence as low; this hub translates that into an ingredient-level verdict with safety and hype context - not individualized recommendations.
Insufficient evidenceEv 48Hype 64
Agmatine
52
Arginine metabolite marketed for pumps and mood; human data are early and mixed. We summarize evidence, safety, and hype as editorial context-not medical advice.
Mixed evidenceEv 46Hype 60
L-Ornithine
52
Amino acid in urea cycle; fatigue and athletic recovery claims have thin human evidence. We summarize evidence, safety, and hype as editorial context-not medical advice.
Mixed evidenceEv 48Hype 56

Common questions in this category

Focused pages tied to ingredients below - use them to jump into safety, efficacy, and context.

Acetyl-L-carnitine
Acetyl-L-carnitine benefits
Acetyl-L-carnitine
Acetyl-L-carnitine side effects
Acetyl-L-carnitine
Does Acetyl-L-carnitine work?
Acetyl-L-carnitine
Is Acetyl-L-carnitine legit?
Acetyl-L-carnitine
Is Acetyl-L-carnitine safe?
Acetyl-L-carnitine
Should I take Acetyl-L-carnitine?
Agmatine
Agmatine benefits
Agmatine
Agmatine side effects
Agmatine
Does Agmatine work?
Agmatine
Is Agmatine legit?
Agmatine
Is Agmatine safe?
Agmatine
Should I take Agmatine?
BCAAs (leucine/isoleucine/valine)
BCAAs (leucine/isoleucine/valine) benefits
BCAAs (leucine/isoleucine/valine)
BCAAs (leucine/isoleucine/valine) side effects
BCAAs (leucine/isoleucine/valine)
Does BCAAs (leucine/isoleucine/valine) work?
BCAAs (leucine/isoleucine/valine)
Is BCAAs (leucine/isoleucine/valine) legit?

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Where readers often start

Comparisons inside this category

Creatine

Whey protein

Beta-alanine

Leucine

Casein protein

Essential amino acids (EAAs)

L-citrulline

Taurine

Betaine anhydrous

Glycine

BCAAs (leucine/isoleucine/valine)

EAAs (essential amino acid blends)

L-Leucine

Pea protein isolate

Rice protein isolate

L-Lysine

L-tyrosine

L-glutamine

Collagen peptides

L-carnitine

HMB (β-hydroxy β-methylbutyrate)

L-arginine

L-tryptophan

Acetyl-L-carnitine

Carnosine

Collagen peptides (hydrolyzed)

Hemp protein

L-Proline

Agmatine

L-Ornithine

Common questions in this category