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

Arizona State University (ASU)

Status: Completed

Conditions: Insulin Resistance

Treatments: Other: sourdough bread 72; Other: sourdough bread 48; Other: yeast bread; Other: sourdough bread 24

Study type: Interventional

Funder types: Other

Identifiers

NCT06925451

STUDY00021470

Details and patient eligibility

About

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.

Full description

Sourdough bread has been proven to have higher fiber content and contains beneficial microorganisms from the fermentation process and has been linked to reduced risk of various diseases like diabetes, cardiovascular disease, and dyslipidemia. The fermentation of sourdough bread products converts starch and sugar in the dough into resistant starches and other slower digesting compounds. Sourdough bread products also have a lower glycemic index value, meaning they do not cause the blood sugar to rise as quickly, thus slowing the release of insulin in the body, leading to reduced risk of insulin resistance. However, very few studies exist studying the effects of naturally fermented sourdough products in individuals with prediabetes. It is worth exploring if increasing the fermentation time of naturally fermented sourdough bread increases the effects on relevant biomarkers relating to postprandial glycemia and insulinemia in prediabetic adults.

This study examined the acute effect of varying lengths of sourdough fermentation times on postprandial blood glucose levels over a 4-week period in adults with prediabetes (as evidenced by fasting glucose ≥100 or diagnosis by physician), but not taking diabetic medications. For each trial, the sourdough bread was ingested after an overnight fasting period in order to evaluate the effects of the bread when incorporated into the diet in place of breads made with baker's yeast. The goal of this crossover randomized trial was to assess the relationship between lengthened fermentation time, meaning an increased amount of lactic acid and acetic acid in the bread product, and glycemic and insulinemic response.

Enrollment: 5 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

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

Exclusion criteria

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

Trial design

Primary purpose: Other

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Single Blind

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5 participants in 4 patient groups

sourdough bread 24

Experimental group

Description:

24 hours fermentation

Treatment:

Other: sourdough bread 24

Control bread

Active Comparator group

Description:

12 hours fermentation

Treatment:

Other: yeast bread

sourdough bread 48

Experimental group

Description:

48 hours fermentation

Treatment:

Other: sourdough bread 48

sourdough bread 72

Experimental group

Description:

72 hours fermentation

Treatment:

Other: sourdough bread 72