Short-chain fatty acids (SFCAs) are products of intestinal microbial fermentation of indigestible foods and include propionate, acetate and butyrate. These SCFAs are the main energy source of colonocytes, making them a key determinant of intestinal epithelial layer health. In addition, SCFAs in the gut have distant effects on the kidney, including the production of reactive oxygen species (ROS), which have been implicated in renal changes that trigger the initiation of crystal formation.