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Essential Amino Acids

Proteins are composed of amino acids, some of which your body can synthesize and others not. The nine you need yet cannot synthesize, and thus need to ingest, are called essential amino acids (EAAs). A protein is said to be complete when it has enough of each EAA.

Our evidence-based analysis on essential amino acids features 4 unique references to scientific papers.

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Summary of Essential Amino Acids

Proteins are composed of amino acids, some of which your body can synthesize and others not. The nine you need yet cannot synthesize, and thus need to ingest, are called essential amino acids (EAAs). Among those, branched-chain amino acids (BCAAs) are crucial to your muscles,[1] with leucine being especially anabolic.

Amino acids: requirements of adults and contents of proteins
Essential Amino Acid (EAA)mg/kg/dayCompleteMilkPeaRiceSoyWhey
Leucine (BCCA)
39
59
97
97
88
80
116
Isoleucine (BCCA)
20
30
50
54
40
43
59
Valine (BCCA)
26
39
58
81
55
44
58
Cystine
4
6
9
14
17
12
20
Histidine
10
15
30
17
24
26
21
Lysine
30
45
80
83
33
60
102
Methionine
10
16
27
5
29
10
23
Methionine + cysteine
15
22
30
8
39
14
36
Phenylalanine + tyrosine
25
30
99
94
111
90
66
Threonine
15
23
47
43
38
37
76
Tryptophan
4
6
13
11
14
13
20

mg/kg/day = daily requirement in milligrams (of a given amino acid) per kilogram (of body weight) per day | Complete/Milk/Pea/Rice/Soy/Whey = milligrams of amino acid per gram of complete/milk/pea/rice/soy/whey protein (mg/g)
References: World Health Organization. Protein and Amino Acid Requirements in Human Nutrition, page 245, table 49. 2007.[2] Kalman. Foods. 2014.[3] Gorissen et al. Amino Acids. 2018.[4] USDA Food Composition Databases (accessed: 2018 Sep)

A protein is called complete when, proportionally to its overall amino-acid content, it has enough of each EAA. The main advantage of animal proteins is that most are complete.

Things to Note

Also Known As

EAAs

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