Artificial sweeteners, also known as sugar substitutes or sugar-free sweeteners, are substances used to replace sugar in foods and beverages. Sugar substitutes are used for many different reasons, including: 1) To aid weight loss – some people choose to limit their dietary energy intake by substituting high-energy sugar or corn syrup for other sweeteners that have little or no nutritional energy. This allows them to eat the same foods they would normally eat while losing weight and avoiding other problems associated with excess calorie intake. 2) In diabetes mellitus. People with diabetes have difficulty regulating their blood sugar. By limiting their sugar intake with artificial sweeteners, they can enjoy a varied diet while carefully controlling their sugar intake. In addition, some sugar substitutes release energy but are metabolized more slowly, meaning blood sugar levels can remain more stable over time.