Essential fatty acid sufficiency does not preclude fat-soluble-vitamin deficiency in short-bowel syndrome. Patients with extensive small-bowel resection may experience malabsorption and nutrient deficiencies. We evaluated the ability to absorb fat and fat-soluble vitamins in a short-gut patient. For 18 wk after stopping intravenous lipid, while consuming a low-lactose, low-fat diet, he exhibited no clinical manifestations of essential fatty acid deficiency (EFAD). Serum 20:4n-6 (20:4 omega-6) and 18:2n-6 fatty acid concentrations were normal, whereas the concentration of 20:3n-9 remained less than or equal to 0.1% of total serum fatty acids. Although serum vitamin A was normal, beta-carotene was undetectable despite oral supplementation. Prothrombin time was elevated until parenteral vitamin K was given. This patient has fat absorption adequate to prevent EFAD but inadequate absorption of fat-soluble vitamins. In patients with short bowel, the requirements for parenteral lipids and fat-soluble vitamins should be determined independently. 