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

This research project aims to provide the scientific findings about the beneficial effects of okara (soybean pulp) consumption on gut and glycaemic health in middle-aged and older individuals in Singapore. In addition, it aims to examine the health promoting impact of bio-transformed okara in this population. We hypothesise that consuming a habitual diet with an okara (untreated or bio-transformed) incorporated food product will improve the gut microbiome composition and will increase the production of short chain fatty acids when compared to a same diet with no okara. Okara-based food product can also improve the glycaemic response in individuals compared to a product without okara in meal tolerance test (acute).

Study Overview

• Status: Active, not recruiting
• Conditions: Aging; Blood Glucose; Microbiota; Gastrointestinal Microbiome
• Intervention / Treatment: Dietary supplement: Okara biscuits; Dietary supplement: Bio-okara biscuits; Dietary supplement: Control biscuits

Detailed Description

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.

• Study Type: Interventional
• Enrollment (Anticipated): 20
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Singapore
  • Singapore, Singapore, 117546
    • Department of Food Science and Technology; National University of Singapore

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 50 years to 75 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

1. Ability to give an informed consent
2. Age 50 to 75 years
3. Willing to follow the study procedures

Exclusion Criteria:

All subjects meeting any of the exclusion criteria at baseline will be excluded from participation

1. Significant change in weight (≥ 3 kg body weight) during the past 3 months
2. Allergy to soy-based products
3. Acute illness at the study baseline
4. Exercising vigorously over the past 3 months
5. Following any restricted diet (e.g. vegetarian)
6. Smoking
7. Have a daily intake of more than 2 alcoholic drinks per day
8. Prescribed and taking antihypertensive/cholesterol-lowering/ type-2 diabetic medication which started less than 5 years prior to the intervention participation
9. Taking dietary supplements which may impact the outcome of interests (e.g. vitamin supplements, probiotic supplement etc.)
10. Pregnant, lactating, or planning pregnancy in the next 6 months
11. Insufficient venous access to allow the blood collection
12. Very high intake of fibre/ vegetables on a daily basis

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Double

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Okara biscuits; Subjects will consume their habitual diet with daily okara biscuit consumption accounting to 20 grams/ day of dry okara powder for 21 days.	Dietary supplement: Okara biscuits; Consumption of okara-enriched biscuits together with habitual diet.
Experimental: Bio-okara biscuits; Subjects will consume their habitual diet with daily bio-okara biscuit consumption accounting to 20 grams/ day of dry bio-okara powder for 21 days.	Dietary supplement: Bio-okara biscuits; Consumption of bio-okara-enriched biscuits together with habitual diet. Bio-okara is a form of fermented okara.; Other Names: Fermented okara biscuits
Experimental: Control biscuits; Subjects will consume their habitual diet with daily control biscuit consumption for 21 days.	Dietary supplement: Control biscuits; Consumption of control biscuits together with habitual diet.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in gut microbiome composition before and after a 3 week intervention.	Gut microbiome composition will be determined via fecal samples of subjects at baseline and after each intervention period.	Baseline and post-intervention (at 3 weeks)
Change in fecal short chain fatty acids (SCFA) before and after a 3 week intervention.	SCFA will be determined via fecal samples of subjects at baseline and after each intervention period.	Baseline and post-intervention (at 3 weeks)
Change in serum short chain fatty acids (SCFA) before and after a 3 week intervention.	SCFA will be determined via serum samples of subjects at baseline and after each intervention period.	Baseline and post-intervention (at 3 weeks)
Change in fecal bile acids before and after a 3 week intervention.	Bile acids will be determined via serum samples of subjects at baseline and after each intervention period.	Baseline and post-intervention (at 3 weeks)
Change in serum zonulin before and after a 3 week intervention.	Serum zonulin will be determined via serum samples of subjects at baseline and after each intervention period.	Baseline and post-intervention (at 3 weeks)
Change in blood glucose levels before and after a 3 week intervention.	Glucose levels will be determined via fasted blood samples of subjects at baseline and after each intervention period.	Baseline and post-intervention (at 3 weeks)
Change in blood insulin levels before and after a 3 week intervention.	Insulin levels will be determined via fasted blood samples of subjects at baseline and after each intervention period.	Baseline and post-intervention (at 3 weeks)
Change in blood triglyceride levels before and after a 3 week intervention.	Total triglyceride levels will be determined via fasted blood samples of subjects at baseline and after each intervention period.	Baseline and post-intervention (at 3 weeks)
Change in blood cholesterol levels before and after a 3 week intervention.	Total cholesterol levels will be determined via fasted blood samples of subjects at baseline and after each intervention period.	Baseline and post-intervention (at 3 weeks)
Change in blood low-density lipoprotein-cholesterol levels before and after a 3 week intervention.	Low-density lipoprotein-cholesterol levels will be determined via fasted blood samples of subjects at baseline and after each intervention period.	Baseline and post-intervention (at 3 weeks)
Change in blood high-density lipoprotein-cholesterol levels before and after a 3 week intervention.	High-density lipoprotein-cholesterol levels will be determined via fasted blood samples of subjects at baseline and after each intervention period.	Baseline and post-intervention (at 3 weeks)
Change in blood glucose levels over acute trial period	Glucose levels will be determined via fasted blood samples of subjects and after consumption of intervention	Time 0, 15, 30, 45, 60, 90, 120, 180, 240 minutes held on pre- intervention arm visit (Every 6 weeks, up to 12 weeks).
Change in blood insulin levels over acute trial period	Insulin levels will be determined via fasted blood samples of subjects and after consumption of intervention	Time 0, 15, 30, 45, 60, 90, 120, 180, 240 minutes held on pre- intervention arm visit (Every 6 weeks, up to 12 weeks).
Change in blood short-chain fatty acids levels over acute trial period	Short-chain fatty acids levels will be determined via fasted blood samples of subjects and after consumption of intervention	Time 0, 15, 30, 45, 60, 90, 120, 180, 240 minutes held on pre- intervention arm visit (Every 6 weeks, up to 12 weeks).
Change in blood amino acid levels over acute trial period	Amino acid levels will be determined via fasted blood samples of subjects and after consumption of intervention	Time 0, 15, 30, 45, 60, 90, 120 minutes held on pre- intervention arm visit (Every 6 weeks, up to 12 weeks).

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in blood pressure	Blood pressure	Baseline and post-intervention (at 3 weeks)
Change in anthropometric measurements	Waist circumference	Baseline and post-intervention (at 3 weeks)
Change in anthropometric measurements	Weight	Baseline and post-intervention (at 3 weeks)
Change in anthropometric measurements	Height	Baseline
Dietary assessment	Dietary questionnaires (3-day food record)	Baseline and post-intervention (at 3 weeks)
Stool assessment	Stool sampling questionnaire will be completed by subjects, which notes down food or alcohol consumed over the past 24 hours prior to collection, any discomfort, pain or bloating, flatulence, noticable changes in stool frequency or consistency, any blood in stool and any type of medication consumed over the past 3 months.	Baseline and post-intervention (at 3 weeks)
Stool assessment	Bristol stool chart (Ranging from Type 1 to Type 7, with Type 3 or 4 being ideal.	Baseline and post-intervention (at 3 weeks)
Sleep quality assessment	Pittsburgh sleep quality index questionnaire, with 7 different components assessing sleep and each component making up a minimum or 0 and maximum of 3 points. The full scale ranges from 0 to 21, with a lower score indicative of a better quality of sleep.	Baseline and post-intervention (at 3 weeks)
Sleep quality assessment	Sleep evaluation questionnaire (survey) to assess eligibility for studies with sleep involved	Baseline and post-intervention (at 3 weeks)
Cognitive assessment	Montreal cognitive assessment	Baseline and post-intervention (at 3 weeks)
Appetite assessment	Visual analogue scale, with unit of measure being units on a scale	Baseline and post-intervention (at 3 weeks)
Change in blood amino acids levels over acute trial period	Amino acid levels will be determined via fasted blood samples of subjects and after consumption of intervention	Time 0, 15, 30, 45, 60, 90, 120 minutes held on pre- intervention arm visit (Every 6 weeks, up to 12 weeks).
Change in blood triglyceride levels over acute trial period	Total triglyceride levels will be determined via fasted blood samples of subjects and after consumption of intervention	Time 0, 15, 30, 45, 60, 90, 120, 180, 240 minutes held on pre- intervention arm visit (Every 6 weeks, up to 12 weeks).
Change in blood cholesterol levels over acute trial period	Total cholesterol levels will be determined via fasted blood samples of subjects and after consumption of intervention	Time 0, 15, 30, 45, 60, 90, 120, 180, 240 minutes held on pre- intervention arm visit (Every 6 weeks, up to 12 weeks).
Change in blood low-density lipoprotein-cholesterol levels over acute trial period	Low-density lipoprotein-cholesterol levels will be determined via fasted blood samples of subjects and after consumption of intervention	Time 0, 15, 30, 45, 60, 90, 120, 180, 240 minutes held on pre- intervention arm visit (Every 6 weeks, up to 12 weeks).
Change in blood high-density lipoprotein-cholesterol levels over acute trial period	High-density lipoprotein-cholesterol levels will be determined via fasted blood samples of subjects and after consumption of intervention	Time 0, 15, 30, 45, 60, 90, 120, 180, 240 minutes held on pre- intervention arm visit (Every 6 weeks, up to 12 weeks).

Collaborators and Investigators

• Sponsor: National University, Singapore
• Collaborators: Ministry of Education, Singapore
• Investigators: Principal Investigator: Jung Eun Kim, National University, Singapore

Publications and helpful links

General Publications

• Vong, W.C., X.Y. Hua, and S.-Q. Liu, Solid-state fermentation with Rhizopus oligosporus and Yarrowia lipolytica improved nutritional and flavour properties of okara. Lwt, 2018. 90: p. 316-322.
• Yogo, T., et al., Influence of Dried Okara-Tempeh on the Composition and Metabolites of Fecal Microbiota in Dogs. International Journal of Applied Research in Veterinary Medicine, 2011. 9(2): p. 176-183.
• Jimenez-Escrig A, Tenorio MD, Espinosa-Martos I, Ruperez P. Health-promoting effects of a dietary fiber concentrate from the soybean byproduct okara in rats. J Agric Food Chem. 2008 Aug 27;56(16):7495-501. doi: 10.1021/jf800792y. Epub 2008 Jul 18.
• Lu, F., Y. Liu, and B. Li, Okara dietary fiber and hypoglycemic effect of okara foods. Bioactive Carbohydrates and Dietary Fibre, 2013. 2(2): p. 126-132.
• Lee DPS, Gan AX, Sutanto CN, Toh KQX, Khoo CM, Kim JE. Postprandial glycemic and circulating SCFA concentrations following okara- and biovalorized okara-containing biscuit consumption in middle-aged and older adults: a crossover randomized controlled trial. Food Funct. 2022 Sep 22;13(18):9687-9699. doi: 10.1039/d2fo00526c.

Study record dates

Study Major Dates

• Study Start (Actual): November 1, 2019
• Primary Completion (Actual): September 28, 2020
• Study Completion (Anticipated): September 1, 2022

Study Registration Dates

• First Submitted: May 24, 2019
• First Submitted That Met QC Criteria: June 5, 2019
• First Posted (Actual): June 6, 2019

Study Record Updates

• Last Update Posted (Actual): March 24, 2022
• Last Update Submitted That Met QC Criteria: March 23, 2022
• Last Verified: March 1, 2022

More Information

Terms related to this study

• Keywords: Microbiota; Glycemic; Gut microbiome; Okara; Soybean pulp; Soybean; Fibre; Gastrointestinal microbiome; Glycaemic; Middle-aged and older adults; Singapore
• Other Study ID Numbers: S4

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No
• IPD Plan Description: Electronic data with any identifiable participant information will be de-identified prior to statistical analysis.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No