Effects of Sourdough Fermentation Duration and Acid Development on Postprandial Blood Glucose in Prediabetic Adults

NCT06925451 | Completed

• 1 other identifier: STUDY00021470
• Study Type: interventional
• Target: 5
• Locations: 1 country
• Sites: 1

Brief Summary

The primary intervention for management of prediabetes is lifestyle changes. Eating healthier and increasing physical activity was found to slow the progression of prediabetes into diabetes, reduce the risk of other diseases like cardiovascular disease and hypertension, and have a lasting impact even after the intervention is discontinued. Studies found that increasing the intake of fiber, pre- and probiotics, and fermented foods have been linked to improved glycemic biomarkers. The goal of this crossover randomized trial is to assess the relationship between lengthened fermentation time of sourdough bread, e.g., an increased amount of lactic acid and acetic acid in the bread product, and postprandial glycemic response in healthy adults with prediabetes.

Conditions

Insulin Resistance

Keywords

fermentation; pre-diabetes; sourdough bread; post-prandial glycemia

Outcome Measures

Primary Outcomes (1)

• blood glucose

  blood glucose will be measured using a glucometer and capillary blood from finger prick

  conducted at fasting and 30, 60, 90, and 120 minutes post-meal

Secondary Outcomes (2)

• hunger rating

  conducted at 120 minutes post-meal

• bread palatability

  conducted at 120 minutes post-meal

Study Arms (4)

sourdough bread 24

EXPERIMENTAL

24 hours fermentation

Other: sourdough bread 24

Control bread

ACTIVE COMPARATOR

12 hours fermentation

Other: yeast bread

sourdough bread 48

EXPERIMENTAL

48 hours fermentation

Other: sourdough bread 48

sourdough bread 72

EXPERIMENTAL

72 hours fermentation

Other: sourdough bread 72

Interventions

sourdough bread 24 OTHER

fermentation time=24 hours

sourdough bread 24

sourdough bread 48 OTHER

fermentation time=48 hours

sourdough bread 48

sourdough bread 72 OTHER

fermentation time=72 hours

sourdough bread 72

yeast bread OTHER

no fermentation

Control bread

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• prediabetes; not on metformin; no known food allergies or sensitivities; not supplementing pre/post biotics

You may not qualify if:

• following diet that restricts carbohydrates; medication use affecting blood glucose; acute illness; smoker; pregnant; lactating; GI tract surgery; not willing to follow protocol

Sponsors & Collaborators

• Arizona State University: lead

Study Sites (1)

850 PBC

Phoenix, Arizona, 85004, United States

Location

MeSH Terms

Conditions

Insulin Resistance; Glucose Intolerance

Condition Hierarchy (Ancestors)

Hyperinsulinism; Glucose Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases; Hyperglycemia

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Purpose: OTHER
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor and Senior Associate Dean

Model Details: The day prior to testing is standardized: no vigorous activity or alcohol consumption, and two bagels are to be consumed between 3 pm and 8 pm. Participants will begin an overnight fast starting around 10 pm (only water is to be consumed). The bagels will be provided at no charge. For each of the 4 test visits, participants arrive in a fasted state and a blood drop will be collected via finger prick to measure glucose. The 'test meal' will be consumed under observation within 8 minutes. The three fermented versions on the sourdough bread and the control bread will be fed using a four-block randomization process. Finger pricks will take place at 30, 60, 90, and 120 minutes post meal. The participant will be asked to complete hunger measures and report on the acceptability of the bread at the completion of testing.

Study Record Dates

• First Submitted: April 6, 2025
• First Posted: April 13, 2025
• Study Start: April 4, 2025
• Primary Completion: August 15, 2025
• Study Completion: December 15, 2025
• Last Updated: January 23, 2026

Record last verified: 2025-08

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)