bleeding), and most often bleeding is attributed to diverticulosis. Female sex is also a risk factor, although this may be due to increased use of NSAIDs in older women with rheumatoid arthritis and other autoimmune arthritis. Studies that address prognostic factors influencing rebleeding, length of stay, and mortality have implicated age older than 70–80 years as a risk for significantly higher mortality and morbidity.71, 72 Continued bleeding or rebleeding are the highest predictors of mortality and morbidity in older patients, as in patients of any age. Management of bleeding in older patients should take into account the severity of the bleeding as measured by cardiovascular stability and a decrease in hemoglobin level. Older patients should be considered for early intervention using endoscopy, surgery, or angiographic vascular embolic treatment due to their reduced cardiovascular reserve.71 To avoid recurrence of bleeding, NSAID use should be avoided if possible and, if present, H pylori should be eradicated. Maintenance therapy with full doses of H2-receptor antagonists or proton pump inhibitors is effective for reducing recurrent hemorrhage from both duodenal and gastric ulcers. Emergent operation for lower GI bleeding is required in 10%–25% of patients, usually due to difficulty in identifying or treating the source of the bleeding using nonsurgical interventions. Operative mortality is low (4%) in patients aged 70 years if appropriately stabilized and operated on without undue delay.73 Small Intestinal Function in Aging The small intestine has a large functional reserve capacity due to the substantial mucosal surface area available for secretion and absorption. Intestinal surface area does not change after 6 weeks of age in rats. It is unclear whether the specific activity of intestinal disaccharidases and aminopeptidases is affected by aging, because both higher and lower activity have been reported in aged animals compared with youthful controls.74 Delayed maturation and expression of brush-border enzymes in small intestinal villous epithelial cells during crypt-to-villous migration seem to be the underlying cause.75 However, absorption of lactose, mannitol, and lipid in individuals older than 60 years is unaffected.76, 77 Vitamin D absorption and sensitivity are significantly impaired in aged rats.78 This is also a concern in human studies, which have documented decreased uptake of vitamin D, folic acid, vitamin B12, calcium, copper, zinc, fatty acids, and cholesterol in aged subjects.79 Recent recommendations by the US Department of Agriculture to increase calcium, vitamin B12, and vitamin D supplementation in persons older than 70 years reflect this new information. Iron is one nutrient that is usually present in overabundance in the diet for older individuals. Older patients may be at risk for diseases such as hepatic iron overload (particularly in individuals who are monozygotic for hemochromatosis), and iron overload has been implicated in some models of oxidative stress. Older men and postmenopausal women do not require additional iron unless there is superimposed blood loss or bone marrow impairment.80 There is little evidence that older individuals are at risk for impaired absorption of most macronutrients in the absence of superimposed disease or surgical resection of the small bowel. Limited data suggest that absorption of raw and heat-treated soybeans is impaired in old rats compared with youthful animals, whereas casein, skim milk powder, and autoclaved