Metabolic effects of allulose in healthy adults (MAIA)

• Applicant: Dr. Bettina Hieronimus
• Subject Area: Nutritional Sciences
• Term: since 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 517694181

Allulose is a rare sugar that can be used as a sugar substitute. It has properties comparable to sucrose but provides 90-95% less energy. Allulose is already used in food production in several countries and is expected to be approved as a Novel Food within the European Union. Especially animal studies, but also a few human studies suggest that allulose affects satiety, postprandial glucose and body weight. In rodents, oral intake of allulose resulted in an increased secretion of the gut hormone Glucagon-like Peptide 1 (GLP-1), which induces satiety and can support healthy weight regulation. In humans, application of allulose via a gastric tube led to an increase in GLP-1 levels, however it had no effect on gastric emptying or satiety. GLP-1 also acts as an incretin and facilitates glucose-dependent insulin secretion from the pancreas. Further, animal studies showed that consumption of allulose increases hepatic glucose disposal and subsequently lowers postprandial blood glucose levels. If confirmed, allulose might support blood glucose regulation. Consumption of allulose with a high fat diet prevented diet-induced weight gain in animal studies. The consumption of small amounts of allulose for 12 weeks daily in addition to a self-selected ad libitum diet resulted in moderate weigh loss in humans. This project will study the effect of allulose consumption in humans on the following outcomes – satiety, blood glucose regulation and body weight and composition. The study will be a double blinded, crossover intervention study with two interventions where 12 healthy women and men (age 18-50, BMI 18,5-30 kg/m2) will consume three beverages daily sweetened with allulose or aspartame (control) for 4 weeks. All procedures will be performed during a 7-day long baseline phase and repeated at the end of the 4-week intervention. Effects of allulose on satiety and GLP-1, as well as other gut hormones, will be assessed after a controlled meal-challenge. Effects on blood glucose regulation will be measured via oral glucose tolerance tests (Matsuda-Index) and with the aid of continuous glucose monitoring over 7 days. Changes in body weight and composition (bioelectrical impedance analysis) will be assessed. Clinical trials with clearly defined outcomes and administering realistic doses of allulose over longer time frames are missing. The proposed project will close this gap and assess if the consumption of physiological amounts of allulose in a real-life setting affects postprandial GLP-1 secretion, blood glucose regulation and body weight and composition. These findings are of high importance as allulose will likely be used in food production in Germany and Europe.

• DFG Programme: Research Grants