There are two widely used low-calorie alternatives to sugar for people on low-calorie diets. Saccharine is derived from coal tar and is much sweeter than sugar. Usually available as a liquid or powder, it can be used in some recipes calling for sugar, but not for syrups. Aspartame, also called by the brand name Nutrasweet, is 200 times sweeter than sugar and so used in much smaller quantities. It cannot be heated, but it can be used to sweeten cold desserts and drinks.