This gene encodes the ileal fatty acid binding protein. Fatty acid binding proteins are a small, highly conserved cytoplasmic protein family that can bind to long-chain fatty acids and other hydrophobic ligands. Ileal proteins stimulate the secretion of gastric acid and pepsinogen, which may be important for maintaining bile acid homeostasis. Isoform 2 is crucial for the survival of colon cancer cells in bile acid-induced apoptosis.