Impact of Okara and Bio-okara Food Product on Gut and Glycaemic Health in Middle-aged and Older Adults in Singapore

For this double‐blind, randomized, crossover experiment, the participants will complete a 16‐week study period. Following a 1‐wk pre‐intervention baseline period, each participant will be randomly assigned to consume their habitual diet that either contains or do not contain okara food product (untreated and bio‐transformed okara) for 3 weeks. The food product will be equivalent to a consumption of 20 g of okara (dried) per day. Following a 3‐week dietary 'washout' period, the participants will be assigned to consume the other diets for another 3 weeks. This process will be repeated until each participant have completed all three interventions. Fecal and fasting‐state blood samples will be obtained at study weeks 1, 4, 7, 10, 13, and 16, which correspond to before and end of the three 3‐week intervention periods. Additionally, during Weeks 1, 7 and 13, fasted participants will also be required to undergo a meal tolerance test. A cannula will first be inserted into the participant's forearm for blood sampling by a trained phlebotomist. One of three meals prepared by designated study personnel will then be randomly assigned during each visit, namely, control biscuit, untreated okara biscuit and bio‐transformed okara biscuit. During each test, the participants will eat the prepared meal within 10 minutes and have blood samples drawn by intravenous cannulation at time = 0, 15, 30, 45, 60, 90, 120, 180 and 240 min, with time 0 being the time the participants first start eating the biscuits. The blood samples will analyzed for the postprandial blood glucose, insulin responses and lipid levels.