D-allulose, also known by the name D-psicose or just allulose, is a rare keto-sugar epimer of D-fructose in the third carbon (C 3 ), and naturally occurs in small quantity in fruits such as grapes and figs. It is low calorie sweetener produced enzymatically from D-fructose by enzymes D-ketose 3-epimerase (DKEase) family. D-allulose has a similar taste, texture and functionality as sweetener comparing to high calorie sweetener sugar table sucrose. D-allulose is poorly metabolized in the body with minimal impact on blood sugar levels making it a natural low-calorie sweetener. This property makes D-allulose an attractive sweetener for diabetes and for body weight management. Laboratory studies on D-allulose intake demonstrated its safety with no significant adverse effects. United States Food and Drug Administration (FDA) has granted D-allulose the status of Generally Recognized as Safe (GRAS). Plus, it is considered safe for human consumption by regulatory organizations in other countries except in European Union due to their request for further laboratory testing. Maximum acceptable daily intake of D-allulose is 0.9 grams per kilogram body weight. Excessive intake for more than the recommended daily intake could lead to some side effects such as gastrointestinal discomfort or laxative effects. In general, D-allulose is considered one of the preferred natural low calories sweeteners for those seeking an alternative to table sugar sucrose.
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