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 Mager, D. R. Articles by Pencharz, P. B. Search for Related Content PubMed PubMed Citation Articles by Mager, D. R. Articles by Pencharz, P. B.

---

Nutrient Requirements

Branched-Chain Amino Acid Requirements in School-Aged Children Determined by Indicator Amino Acid Oxidation (IAAO)^1,2

Diana R. Mager^*,**, Linda J. Wykes, Ronald O. Ball^**, and Paul B. Pencharz^*,**,,,3

Departments of ^* Nutritional Sciences, and Paediatrics, University of Toronto; ^** The Research Institute, The Hospital for Sick Children, Toronto, Canada M5G 1X8; School of Dietetics and Human Nutrition, McGill University, Ste-Anne-de-Bellevue, Canada H9X 3V9; and Department of Agricultural, Food and Nutritional Sciences, University of Alberta, Edmonton, Canada T6G 2P5

³To whom correspondence should be addressed. E-mail: paul.pencharz{at}sickkids.ca.

The current WHO/FAO/UNU recommendations for BCAA requirements in school-aged children are based on nitrogen balance studies that have tended to produce lower estimates of amino acid requirements that those determined using stable isotope methodologies. The new dietary reference intake (DRI) recommendations for total BCAA requirements in children were determined using a factorial approach that included adult BCAA requirements plus the additional needs for growth. The purpose of this study was to determine directly total BCAA requirements in school children aged 6–10 y using indicator amino acid oxidation (IAAO). Five children (8.5 ± 1.2 y) were assigned randomly to receive 7 graded intakes of total BCAA. Individual BCAA in the test diet were provided in the same proportions as those present in egg protein to minimize the potential interactive effects of individual BCAA on assessment of requirement. Total BCAA requirement was determined by measuring the oxidation of L-[1-¹³C] phenylalanine to ¹³CO₂ [F¹³CO₂ in µmol/(kg · h)], after a primed, continuous infusion of the labeled tracer and using a two-phase linear crossover regression analysis. The mean requirement and the population-safe intake level (upper limit of the 95% CI) of the total BCAA in healthy school aged children were 147 and 192 mg/(kg · d), respectively. The estimated mean requirements of the total BCAA as determined by IAAO is 48% higher than the current DRI recommendations, suggesting that these recommendations may be too low to meet the needs of school-aged children.

KEY WORDS: • indicator amino acid oxidation • amino acid requirements • children

This article has been cited by other articles:

				R. Elango, R. O. Ball, and P. B. Pencharz Indicator Amino Acid Oxidation: Concept and Application J. Nutr., February 1, 2008; 138(2): 243 - 246. [Abstract] [Full Text] [PDF]

				M. A Humayun, R. Elango, R. O Ball, and P. B Pencharz Reevaluation of the protein requirement in young men with the indicator amino acid oxidation technique Am. J. Clinical Nutrition, October 1, 2007; 86(4): 995 - 1002. [Abstract] [Full Text] [PDF]

				R. Elango, M. A Humayun, R. O Ball, and P. B Pencharz Lysine requirement of healthy school-age children determined by the indicator amino acid oxidation method Am. J. Clinical Nutrition, August 1, 2007; 86(2): 360 - 365. [Abstract] [Full Text] [PDF]

				M. A. Humayun, R. Elango, S. Moehn, R. O. Ball, and P. B. Pencharz Application of the Indicator Amino Acid Oxidation Technique for the Determination of Metabolic Availability of Sulfur Amino Acids from Casein versus Soy Protein Isolate in Adult Men J. Nutr., August 1, 2007; 137(8): 1874 - 1879. [Abstract] [Full Text] [PDF]

				M. A Humayun, J. M Turner, R. Elango, M. Rafii, V. Langos, R. O Ball, and P. B Pencharz Minimum methionine requirement and cysteine sparing of methionine in healthy school-age children. Am. J. Clinical Nutrition, November 1, 2006; 84(5): 1080 - 1085. [Abstract] [Full Text] [PDF]

				D. R. Mager, L. J. Wykes, E. A. Roberts, R. O. Ball, and P. B. Pencharz Mild-to-Moderate Chronic Cholestatic Liver Disease Increases Leucine Oxidation in Children J. Nutr., April 1, 2006; 136(4): 965 - 970. [Abstract] [Full Text] [PDF]

				J. M Turner, M. A Humayun, R. Elango, M. Rafii, V. Langos, R. O Ball, and P. B Pencharz Total sulfur amino acid requirement of healthy school-age children as determined by indicator amino acid oxidation technique Am. J. Clinical Nutrition, March 1, 2006; 83(3): 619 - 623. [Abstract] [Full Text] [PDF]

				D. R. Mager, L. J. Wykes, E. A. Roberts, R. O. Ball, and P. B. Pencharz Branched-Chain Amino Acid Needs in Children with Mild-to-Moderate Chronic Cholestatic Liver Disease J. Nutr., January 1, 2006; 136(1): 133 - 139. [Abstract] [Full Text] [PDF]

				D. H. Baker Inaugural Article: Comparative nutrition and metabolism: Explication of open questions with emphasis on protein and amino acids PNAS, December 13, 2005; 102(50): 17897 - 17902. [Abstract] [Full Text] [PDF]

				D. H. Baker Tolerance for Branched-Chain Amino Acids in Experimental Animals and Humans J. Nutr., June 1, 2005; 135(6): 1585S - 1590S. [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]

				P. B. Pencharz and R. O. Ball Amino Acid Needs for Early Growth and Development J. Nutr., June 1, 2004; 134(6): 1566S - 1568S. [Abstract] [Full Text] [PDF]