EXCRETION OF AMINO-ACID-RESIDUES FROM DIETS BASED ON LOW-FIBER WHEAT OR HIGH-FIBER RYE BREAD IN HUMAN-SUBJECTS WITH ILEOSTOMIES

Objectives: The effect of consumption of a wheat-flour bread-based low -fibre diet (13.6 g/day fibre per portion) or a rye bran bread and who le-grain rye crispbread-based high-fibre diet (43.5 g/day fibre per po rtion) on the ileal excretion of amino acid residues and crude protein was studied. Design: The study was performed as a cross-over design. Setting: The subjects were studied as outpatients except on the sampli ng days when all subjects were admitted to the research ward and staye d in a nearby patient hotel overnight. Subjects: Six men and two women , all proctocolectomised for ulcerative colitis, volunteered to partic ipate in the study. Interventions: During each dietary period of 3 wee ks, food and excreta were collected and analysed on days 3, 17 and 18. Results: The excretion of crude protein and amino acids (free and bou nd) was generally higher during the high-fibre diet period, although t he relative proportion of amino acids was similar in the ileal effluen ts from the two diets. The apparent digestibilities of crude protein a nd all amino acids except histidine, tyrosine and iii proline were sig nificantly (P < 0.05) lower during the high-fibre diet period. Conclus ion: It was indicated that the effect of the high-fibre rye-based diet was a generally impaired ileal amino acid absorption. Sponsorship: Th is project was supported by the Swedish Council of Forestry and Agricu ltural Research (SJFR) and Wasabrijd AB. Descriptors: amino acids, dig estibility, human, ileostomy, rye.