title: A comparison of fasting serum amino acid profiles of young and elderly subjects.
abstract: The fasting serum amino acid profile in 37 healthy young women and men (30-35 years) was compared with the fasting profile in 30 institutionalized elderly women and men (80-89 years), an ambulatory, self-fed senior-residence group. Levels of serum lysine, leucine, methionine, valine, and total essential amino acids were significantly lower in the older group than in the younger group; however, citrulline and hydroxyproline were significantly higher in the older group compared to the younger group. Histidine, threonine, tryptophan, and the ratio of tryptophan to large neutral amino acids (isoleucine, leucine, phenylalanine, tyrosine, and valine) were also generally lower in the older group than in the younger group, while the difference due to age was more pronounced in the females compared to males. The essential/nonessential amino acid ratio was lower in females compared to males.
authors.affiliation: Bureau of Nutritional Sciences, Health Protection Branch, Tunney's Pasture, Ottawa.
authors.forename: G
authors.initials: G
authors.lastname: Sarwar
authors.forename: H G
authors.initials: HG
authors.lastname: Botting
authors.forename: M
authors.initials: M
authors.lastname: Collins
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000596:Amino Acids / Q000097:blood*; D001798:Blood Proteins / Q000032:analysis; D001806:Blood Urea Nitrogen; D002853:Chromatography, Liquid; D005215:Fasting / Q000097:blood*; D005260:Female; D006707:Homes for the Aged; D006801:Humans; D008297:Male; D015999:Multivariate Analysis; D012016:Reference Values; D012709:Serum Albumin / Q000032:analysis; D012737:Sex Factors; D011795:Surveys and Questionnaires
chemical_list: D000596:Amino Acids; D001798:Blood Proteins; D012709:Serum Albumin