Methods and compositions for regulating fatty acid uptake and/or decreasing gastric motility in an animal are provided. The method comprises administering an antagonist of integrin αvβ3 or αvβ5 to an animal in an amount sufficient to reduce fatty acid uptake in the animal, thereby reducing fatty acid uptake in the animal. In some embodiments, the antagonist is an antibody. Also provided is a method of increasing fatty acid uptake and/or gastric motility in an animal.