Small bowel morphometry was studied in 25 subjects under the age of 70 years and 22 over the age of 70. There was no evidence of malabsorption or malnutrition in either group. Two distal duodenal endoscopic biopsy specimens were examined morphometrically. There were no significant correlations between age and areas of duodenal surface epithelium, crypts and lamina propria, heights of villi and surface epithelium, depth of crypts, crypt to villus ratio, number of intraepithelial lymphocytes, duodenal architecture, enterocytes, brush border and Brunner glands. Contrary to previous reports there was no evidence for a significant effect of age on proximal small bowel morphometry.