Estimation of the renal net acid excretion by adults consuming diets containing variable amounts of protein

Am J Clin Nutr. 1994 Jun;59(6):1356-61. doi: 10.1093/ajcn/59.6.1356.


The object of this study was to determine whether it is possible to reliably estimate the renal net acid excretion (NAE) produced by adults consuming different amounts of dietary protein. A physiologically based calculation model that corrects for intestinal absorption of minerals and sulfur-containing protein and assumes a rate of urinary excretion of organic acids proportional to body surface area was used to estimate NAE. Urinary excretion of different minerals and NAE was measured during the last 48 h of each of four separate 5-d diet periods in six healthy adults. On the basis of food tables, the four nearly isoenergetic diets (one lacto-vegetarian and one high- and two moderate-protein diets) were estimated to yield the following NAE values: 3.7, 117.5, 62.2, and 102.2 mEq/d, respectively. The analytically determined urinary NAE (24.1 +/- 10.7, 135.5 +/- 16.4, 69.7 +/- 21.4, and 112.6 +/- 10.9 mEq/d) corresponded reasonably well to these estimates, suggesting that the calculation model is appropriate to predict the renal NAE from nutrient intake and anthropometric data.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acids / urine*
  • Adult
  • Dietary Proteins / administration & dosage
  • Dietary Proteins / metabolism*
  • Female
  • Humans
  • Kidney / metabolism*
  • Male
  • Models, Theoretical


  • Acids
  • Dietary Proteins