Sweeter Than Table Sugar
Acesulfame potassium	200 times	Is abbreviated as acesulfame K on food labels.  This is calroie-free and used in sweetened foods, beverages, and baked products.  Acesulfame potassium is not broken down by the body and thus, eliminated without providing any calories.
Aspartame	200 times	It is made by joining the amino acid,  asparatic acid and the amino acid methyl ester of phenylalanine.  The components is found naturally in nature and is metabolized the same as the naturally occuring components.  Persons with phenylketonuria (PKU) must control its intake as they cannot metabolize the phenylalanine.  Label must indicate the small amount of phenylalanine in aspartame.
Neotame	7,000 to 13,000 times	It can be used alone or blended with other high-intensity or carbohydrate sweeteners.  The product does not require special PKU labeling as it is not metabolized to phenylalanine.
Saccharin	300 times	This is calorie free.  It's suitable for cooking and baking.  It is not broken down by the body and is eliminated without providing any calories.  Decades ago, there were questions about whether saccharin could cause bladder cancer, based on animal studies.  Since then, numerous studies with animals and humans have shown no overall association between saccharin consumption and cancer incidence.  Saccharin was recently removed from a government list of potential cancer-causing agents.
Sucralose	600 times	Has a brand name of Splenda, and is made from rearanged molecules.  Sucralose can be used in foods and beverages, and for cooking and baking.  The body does not recorgnize sucralose as a sugar or a carbohydrate so it does not metabolizes it, making, it suitable for those with diabetes.
Reduced-Calorie sweeteners	Varies	These are metabolized more slowly than table sugar or incompletely by the body and, thus, provide fewer calories.  They vary in sweetness and are frequently combined with acesulfame potassium, aspartame, saccharin and sucralose.  These combinations are used in sugar-free chewing gums, candies, frozen desserts and baked goods.  Reduced-calorie sweeteners give these foods mild sweetness as well as the bulk and texture of sugar, the intense, low-calorie sweeteners raise the sweetness to the level consumers expect.
Polyols	Varies	These sugar alcohols are reduced-calorie sweeteners that contain some calories.  Polyols are found naturally in berries, apples, plums and other foods, and are manufactured from carbohydrates for use in sugar-free candy, cookies, chewing gum and other reduced-calorie foods.  Familiar names for polyols include isomalt, mannitol, and sorbitol.
Tagatose	varies	This naturally occurring, reduced-calorie bulk sweetener that can be found in some dairy products.  Tagatose has a physical bulk similar to table suigar and is almost as sweet; however it has only 1.5 calories per gram whereas table sugar has 4 calories per gram.

Maasdam, Sharon. 2002December 31. Sweeteners provide lost of flavor but few, or no, calories. FOODday. The Sunday Oregonian, FD6. [Adapted from]

Updated: Saturday, December 29, 2007.