In order to evaluate impairment of exocrine pancreatic function during aging, 27 subjects (mean age: 36 years +/- 7.8) and 28 subjects (mean age: 72 years +/- 3.2), with no clinical or radiological evidence of digestive disease, were selected. Duodenal aspirates over a 60 min period were obtained during continuous IV infusion of secretin (0.5 U/kg/h) and caerulein (75 ng/kg/h). Bicarbonate, lipase, chymotrypsin amylase concentrations and output were measured. Bicarbonate, lipase, chymotrypsin concentrations in the aged group were significantly reduced by 17%, 15% and 23% respectively (P less than 0.05) as compared with those in the young group. In addition, a significant reduction of approximately 45% in bicarbonate and enzyme output levels was observed. This study provides strong evidence for a marked functional involution of the exocrine pancreatic secretion during aging. The potential consequences of this phenomenon on the nutritional status in the elderly are discussed.