The malabsorption and intolerance of glucose and galactose is due to a genetic abnormality, but may also exist in mild form in adults (see glucose & galactose intolerance or galactosemia). In glucose and galactose intolerance avoid ingestion of glucose and galactose, as well as sugars containing them (e.g. lactose, sucrose).
This means avoiding table sugar and milk sugar in all forms, such as sugar cane and sugar beets, sorghum, confectioners’ sugar or powdered sugar, rock candy, brown sugar (made of white sugar and molasses), cotton candy, maple syrup, Demerara and Barbados sugar, molasses, pancake syrup, gingerbreads, baked beans and pumpernickel breads, as well as dairy products. In galactosemia, galactose and lactose must be strictly avoided. Expert dietary advice is required to implement these complicated dietary regimens.