Amino Acids & Proteins

Isolated amino acids, peptides and protein powders. The sports-nutrition end of this group has unusually good trial evidence; the longevity end has almost none.

33 entries

5-HTP (5-hydroxytryptophan)Griffonia simplicifolia Acetyl-L-carnitineThe acetylated form of carnitine, which crosses the blood-brain…Beta-alanineA non-proteinogenic amino acid that is the rate-limiting precursor…Betaine anhydrous (TMG)Trimethylglycine, a methyl donor found in beetroot, wheat bran and…Branched-chain amino acids (BCAAs)The three branched-chain essential amino acids — leucine, isoleucine…Casein proteinThe dominant protein of milk, making up about 80% of milk protein.…Citrulline malateA salt of citrulline and malic acid, usually in a 2:1 ratio by weight…Collagen peptidesCollagen from bovine hide, porcine skin, fish skin or chicken…Creatine hydrochlorideCreatine bound to hydrochloric acid, producing a far more…Creatine monohydrateA compound synthesised in the body from arginine, glycine and…Essential amino acids (EAAs)A blend of the nine amino acids the body cannot synthesise, supplied…GABA (gamma-aminobutyric acid)The principal inhibitory neurotransmitter of the mammalian central…GelatinCollagen partially hydrolysed to the point where it dissolves in hot…GlutathioneA tripeptide of glutamate, cysteine and glycine, and the principal…GlycineThe smallest amino acid, non-essential but required in large amounts…HMB (beta-hydroxy beta-methylbutyrate)A metabolite of leucine, roughly 5% of which is converted to HMB in…L-arginineA conditionally essential amino acid and the direct substrate for…L-carnitineA compound synthesised from lysine and methionine that transports…L-citrullineA non-protein amino acid found in watermelon and produced in the urea…L-glutamineThe most abundant free amino acid in blood and muscle, and the…L-leucineAn essential branched-chain amino acid and the principal amino acid…L-lysineAn essential amino acid abundant in animal protein and legumes and…L-theanineA non-protein amino acid found almost exclusively in tea and in a few…L-tryptophanAn essential amino acid and the dietary precursor to serotonin and…L-tyrosineA non-essential amino acid and the precursor to dopamine,…N-acetylcysteine (NAC)An acetylated form of the amino acid cysteine, used as a mucolytic…Pea proteinPisum sativum Rice proteinOryza sativa SAMe (S-adenosylmethionine)The universal methyl donor of human metabolism, formed from…Soy proteinGlycine max TaurineA sulfur-containing amino acid that is not incorporated into protein,…Whey protein concentrateThe protein fraction of milk whey, filtered to between 35% and 80%…Whey protein isolateWhey processed further to at least 90% protein, removing most of the…

Every entry rates its claims against the human research attached to them, and reports doses as what trials administered rather than as a recommendation. How we rate evidence.