Requirements for indispensable amino acids in adult humans: Longer-term amino acid kinetic study with support for the adequacy of the Massachusetts Institute of Technology amino acid requirement pattern

J. S. Marchini, J. Cortiella, T. Hiramatsu, T. E. Chapman, V. R. Young

Research output: Contribution to journalArticle

43 Scopus citations


Twenty young men received an L-amino acid diet, supplying 140 mg N · kg- 1 · d-1 and patterned as in the Egg diet for 1 wk, and then for 3 wk either a pattern based on international recommendations (modified FAO diet; n = 7), our new amino acid requirement pattern (MIT diet; n = 7), or the egg pattern (Egg diet; n = 6). At the end of the initial week, at 1 and 3 wk with the three experimental diets, and after 3 d after return to the Egg diet, an 8-h continuous intravenous infusion with [1-13C]leucine (3 h fast, 5 h fed while subjects received hourly meals supplying the equivalent of one-twelfth the daily intake) was conducted. After 3 wk with the different diets, mean daily leucine balances were lower (P < 0.01) with the FAO diet (-160 μmol · kg-1 · d-1) than with the MIT diet (-15 μmol · kg-1 · d-1). Together with changes in plasma amino acid profiles [eg, methionine increased (P < 0.05) during feeding with the FAO and Egg diets but not with the MIT diet; increased proline concentrations during the fed state (P < 0.05) with the FAO diet but not with the MIT or Egg diets] we interpret these findings to indicate that the FAO diet is not capable of maintaining amino acid homeostasis, as is the case with the MIT and Egg diets.

Original languageEnglish (US)
Pages (from-to)670-683
Number of pages14
JournalAmerican Journal of Clinical Nutrition
Issue number5
StatePublished - Jan 1 1993
Externally publishedYes



  • Amino acid requirements
  • healthy adult men
  • leucine
  • nitrogen balance
  • oxidation balance
  • plasma amino acids

ASJC Scopus subject areas

  • Medicine (miscellaneous)
  • Nutrition and Dietetics

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