QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Reeds, P. J. Search for Related Content PubMed PubMed Citation Articles by Reeds, P. J.

---

Supplement

Dispensable and Indispensable Amino Acids for Humans^{1 ,2}

U.S. Department of Agriculture/ARS Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030

Here, we compared the traditional nutritional definition of the dispensable and indispensable amino acids for humans with categorizations based on amino acid metabolism and function. The three views lead to somewhat different interpretations. From a nutritional perspective, it is quite clear that some amino acids are absolute dietary necessities if normal growth is to be maintained. Even so, growth responses to deficiencies of dispensable amino acids can be found in the literature. From a strictly metabolic perspective, there are only three indispensable amino acids (lysine, threonine and tryptophan) and two dispensable amino acids (glutamate and serine). In addition, a consideration of in vivo amino acid metabolism leads to the definition of a third class of amino acids, termed conditionally essential, whose synthesis can be carried out by mammals but can be limited by a variety of factors. These factors include the dietary supply of the appropriate precursors and the maturity and health of the individual. From a functional perspective, all amino acids are essential, and an argument in favor of the idea of the critical importance of nonessential and conditionally essential amino acids to physiological function is developed.

KEY WORDS: • amino acid nutrition • metabolism • dietary requirement • function

This article has been cited by other articles:

				Y. Lamers, J. Williamson, L. R. Gilbert, P. W. Stacpoole, and J. F. Gregory III Glycine Turnover and Decarboxylation Rate Quantified in Healthy Men and Women Using Primed, Constant Infusions of [1,2-13C2]Glycine and [2H3]Leucine J. Nutr., December 1, 2007; 137(12): 2647 - 2652. [Abstract] [Full Text] [PDF]

				M. Smriga Letter to the editor Human and Experimental Toxicology, October 1, 2007; 26(10): 833 - 834. [PDF]

				V. H. Castellanos, M. D. Litchford, and W. W. Campbell Modular Protein Supplements and Their Application to Long-Term Care Nutr Clin Pract, October 1, 2006; 21(5): 485 - 504. [Abstract] [Full Text] [PDF]

				B. Desvergne, L. Michalik, and W. Wahli Transcriptional Regulation of Metabolism Physiol Rev, April 1, 2006; 86(2): 465 - 514. [Abstract] [Full Text] [PDF]

				S. C. Kalhan and P. S. Parimi Transamination of Leucine and Nitrogen Accretion in Human Pregnancy and the Newborn Infant J. Nutr., January 1, 2006; 136(1): 281S - 287S. [Abstract] [Full Text] [PDF]

				J.-P. Bonjour Dietary Protein: An Essential Nutrient For Bone Health J. Am. Coll. Nutr., December 1, 2005; 24(suppl_6): 526S - 536S. [Abstract] [Full Text] [PDF]

				N. R. Rodriguez Optimal Quantity and Composition of Protein for Growing Children J. Am. Coll. Nutr., April 1, 2005; 24(2): 150S - 154S. [Abstract] [Full Text] [PDF]

				G. Ravaglia, P. Forti, F. Maioli, G. Bianchi, M. Martelli, T. Talerico, L. Servadei, M. Zoli, and E. Mariani Plasma amino acid concentrations in patients with amnestic mild cognitive impairment or Alzheimer disease Am. J. Clinical Nutrition, August 1, 2004; 80(2): 483 - 488. [Abstract] [Full Text] [PDF]

				S. R. Davis, P. W. Stacpoole, J. Williamson, L. S. Kick, E. P. Quinlivan, B. S. Coats, B. Shane, L. B. Bailey, and J. F. Gregory III Tracer-derived total and folate-dependent homocysteine remethylation and synthesis rates in humans indicate that serine is the main one-carbon donor Am J Physiol Endocrinol Metab, February 1, 2004; 286(2): E272 - E279. [Abstract] [Full Text] [PDF]

				A. V Kurpad, M. M Regan, D. Nazareth, S. Nagaraj, J. Gnanou, and V. R Young Intestinal parasites increase the dietary lysine requirement in chronically undernourished Indian men Am. J. Clinical Nutrition, December 1, 2003; 78(6): 1145 - 1151. [Abstract] [Full Text] [PDF]

				V. R. Young Introduction to the 2nd Amino Acid Assessment Workshop J. Nutr., June 1, 2003; 133(6): 2015S - 2020. [Abstract] [Full Text] [PDF]

				V. R. Young and A. M. Ajami Glutamine: The Emperor or His Clothes? J. Nutr., September 1, 2001; 131(9): 2449S - 2459. [Abstract] [Full Text] [PDF]

				V. R. Young and S. Borgonha Nitrogen and Amino Acid Requirements: : The Massachusetts Institute of Technology Amino Acid Requirement Pattern J. Nutr., July 1, 2000; 130(7): 1841S - 1849. [Abstract] [Full Text]