Fatty Acid-Binding Protein 2 (FABP2) is a cytoplasm protein that belongs to the Fatty-acid binding protein (FABP) family of calycin superfamily. Fatty acid binding proteins are a family of small, highly conserved, cytoplasmic proteins that bind long-chain fatty acids. FABP2 is expressed in the small intestine and at much lower levels in the large intestine, the highest expression levels in the jejunum. FABP2 binds saturated long-chain fatty acids with a high affinity, but binds with a lower affinity to unsaturated long-chain fatty acids. FABP2 is probably involved in triglyceride-rich lipoprotein synthesis and may also help maintain energy homeostasis by functioning as a lipid sensor.