Novel Allulose Amino Acid-containing Sugar-free Beverage Results In Rapid Ad-libitum Rehydration Following Exercise-induced Dehydration

OBJECTIVES: Oral rehydration solutions (ORS) effectively improve hydration status in healthy individuals. While traditional ORS beverages rely on sugar to accelerate hydration, other ingredients may provide a similar effect. Allulose, a rare naturally occurring sugar with nearly zero calories, could support hydration. This study aimed to assess the effectiveness of ad-libitum rehydration using commercially available ORS drinks sweetened with sugar or allulose. METHODS: On three separate occasions, twenty young, active, and healthy adults (9 females) completed a two-hour exercise-induced dehydration protocol in the heat (31 ± 1 °C), followed by a 4-hour ad-libitum rehydration. Trials were identical, the only difference being the drink ingested for rehydration. The three commercially available drinks enriched with 10 g/L of 99.9% deuterium oxide were: a) sugar-sweetened ORS (SS-ORS), b) allulose sugar-free sweetened amino acid ORS (SF-ORS), & c) water (W). EID at 70% of the estimated max heart rate consisted of alternating bouts of cycling & walking exercise for 2 h or until 2% of body weight dehydration. 30 min after the end of the dehydration, subjects were asked to drink 500 mL of fluids, followed by free access to fluids for the remaining 4 h. RESULTS: EID (~2% body weight) did not differ between the trials (P > 0.05). Cumulative fluid intake was significantly greater during the SS-ORS (1,977 ± 733 mL) than W (1,603 ± 567 mL, P < 0.05) but not during the SF-ORS (1878 ± 716 mL, P > 0.05). Fluid absorption (n = 10) based on blood deuterium appearance was significantly faster for SF-ORS at 3 & 3.5 h and was 44 and 41% higher than W, respectively (P > 0.05). Rehydration with the SF-ORS drink led to greater net fluid balance at the 2nd (1.0 ± 0.6%), 3rd (0.8 ± 0.6%), and 4th hour (0.8 ± 0.7%) of rehydration (P < 0.05), compared to W (0.5 ± 1.0, 0.3 ± 0.8%, and 0.2 ± 0.8%). Plasma osmolality and plasma volume were higher during the SF-ORS trial (P < 0.05) than during W at 2, 3, & 4 h of rehydration. Taste perception was significantly higher (P < 0.05) for SS-ORS and SF-ORS drinks than W at 0, 1, & 2 h of rehydration. CONCLUSION: This data indicates that ad-libitum fluid intake with an allulose-sweetened ORS resulted in superior rehydration than water. Using a novel allulose & amino acid ORS could improve utility, especially for those conscious of sugar intake. Supported by: Unilever