D-Fructose is a simple monosaccharide, a ketohexose, and is one of the three dietary monosaccharides along with glucose and galactose. It is the sweetest of all naturally occurring carbohydrates and is found in many fruits, honey, and root vegetables. Its structure is characterized by a ketone functional group at carbon 2. Its primary applications are in the food and pharmaceutical industries. In food, it is widely used as a sweetener, humectant, and flavor enhancer, often in the form of high-fructose corn syrup. In pharmaceuticals and life sciences, fructose serves as a nutritive sweetener in oral liquid formulations, an excipient in tablet manufacturing, and a key biochemical reagent in metabolic studies, particularly related to carbohydrate metabolism and diabetes research. Fructose is also utilized in intravenous solutions for parenteral nutrition. While it provides a rapid energy source, excessive consumption is linked to metabolic disorders. It is generally recognized as safe (GRAS) for use in food.