Estimated Amino Acid requirements of human *
Requirement
(mg./kg of body weight/ day) |
Amino acid pattern
for highquality proteins.-mg/g of proteins** |
Amino
Acids |
Infant
|
Child
|
Man
|
Woman
|
Histidine |
33
|
?
|
?
|
17
|
Isoleucine |
80
|
28
|
12
|
42
|
Leucine |
128
|
42
|
16
|
70
|
Lysine |
97
|
44
|
12
|
51
|
Total sulphur
containing aminoacids |
26
|
45
|
22
|
10
|
Total aroma-tic
amino acids |
132
|
22
|
16
|
73
|
Threonine |
63
|
28
|
8
|
35
|
Tryptophan |
19
|
4
|
3
|
11
|
Valine |
89
|
25
|
14
|
48
|
|
* From Food and Nutrition Board, National Research Council : Improvement
of Protein Nutrient. Washington, D.C. , National Academy of Sciences,
1973.
** 2 g. per kg. of body weight per day of protein of the quality
listed in column 4 would meet the amino acids needs of the infant.
Factors in addition to the age, sex and physiological condition
of an individual influence the requirements for specific amino acids.
If total protein intake is low, small surpluses of certain amino
acids can increase the need for others. The non-essential amino
acids in protein also affect the quality of protein. For example,
the amount of sulphur - containing essential amino acid methionine
required may be somewhat reduced if cystine, a sulphur-containing
non- essential amino acid,is supplied in the diet. Likewise, the
presence in the diet of tyrosine, a non-essential amino acid similar
in structure to phenylalanine, may reduce the requirement for phenylalanine.
Much research has been done on amino acids in recent times and
this has paved the way for dramatic treatment and cure of different
problems by their judicious use.
|