Most patients with chronic inflammatory bowel intolerance disease feel intolerant to different food items and may restrict their diet accordingly. The frequency and pattern of food intolerance did not differ between patients with CD and UC. The food intolerance was probably unspecific rather than of pathogenetic importance.

Gender, age, and body weight are the major determinants of bone mineral density in patients with Crohn's disease. As in healthy individuals, the combined effect of these factors account for up to 50% of the variability in bone mineral density.

The importance of intestinal resection, exclusion of the colon, and steatorrhoea for secondary hyperoxaluria was studied in 81 patients with Crohn's disease and 12 patients with ileostomy after colectomy for ulcerative colitis during a metabolic regime including a fixed oral supply of fat, calcium, and oxalate. Hyperoxaluria (greater than 48 mg (greater than 0.5 mmol) per 24 h) was present in 21 patients with Crohn's disease. All but one half or more of the colon preserved. Renal oxalate excretion was related to the amount of ileum resected. 14C-oxalate absorption was significantly higher in patients with ileal resection and the whole colon preserved than in patients with ileal resection plus hemicolectomy, despite the fact that the latter group had the most extensive ileal resections. Faecal fat and oxalate excretion agreed well in patients without ileostomy (r = 0.76, p less than 0.001), and renal oxalate excretion was significantly higher in patients with steatorrhea and the colon preserved than in patients without steatorrhoea. In all 93 patients 14C-oxalate absorption and renal oxalate excretion was positively correlated with a coefficient of correlation of 0.76 (p less than 0.001). No correlation was present between 47Ca- and 14C-oxalate absorption. The study confirm that a preserved colon is necessary for secondary hyperoxaluria and stresses the importance of ileal resection and steatorrhoea.

The importance of the colon for the absorption of calcium, fat, and fluid was studied in 118 patients with small-bowel resections of various lengths. The patients fell into two groups: 38 with ileostomy and 80 with part of or the whole colon in function. In patients with ileostomy, but not in patients with the colon preserved, the absorption of 47Ca and fluid was inversely correlated to the length of the resected small intestine. In patients with extreme small-bowel resection (greater than or equal to 150 cm) the 47Ca absorption was significantly higher when colon was preserved. In groups of equal small-bowel resections stool mass was significantly higher in patients with ileostomy, but faecal fat was not. However, in both groups faecal fat was correlated to the length of the resected small bowel. The study shows that colon plays an important role for the absorption of calcium after small-intestinal resection and confirms the importance of colon for fluid absorption.

Absorption studies were performed in 17 patients with ulcerative colitis operated on with colectomy and an ileal two-limbed J-pouch anastomosis. The patients were studied 3 and greater than or equal to 18 months after closure of the temporary ileostomy. Increased stool mass (median, 609 g/24 h) was found in all patients and was unchanged with time. Moderate steatorrhoea was present in 29% of the patients 3 months postoperatively, but faecal fat excretion normalized with time. Calcium absorption was normal in all but one patient regardless of time after operation. An abnormal bacterial deconjugation, evaluated by a 14C-glycocholic acid breath test was present in 27% of the patients and increased significantly with time. Forty per cent of the patients had increased faecal bile acid excretion. B12 malabsorption was present in 29-35% of the patients. In conclusion, ileal J-pouch anastomosis for ulcerative colitis causes increased stool mass in all patients and produces moderate bile acid deconjugation and malabsorption in about one-third to half. Substitution therapy with vitamin B12 is necessary in about one-third of the patients. Intestinal adaptation as far as absorption is concerned is minimal after the first 3 postoperative months.