Acute Postprandial Glycemic Responses to Breads Made from Five Commercial Wheat-Flour Formulations: A Small Exploratory Nonrandomized Within-Participant Crossover Study

Background/Objectives: Glycemic responses to bread vary with flour composition and processing; this study compared white bread with four specialty wheat-flour breads consumed in Türkiye.

Methods

This nonrandomized five-condition within-participant crossover study included 12 healthy adults. Test flours were a purple-labeled refined flour formulated with fruit and vegetable extracts and ascorbic acid (not purple wheat), wholemeal einkorn, refined yellow durum, and wholemeal Karakılçık landrace. White bread was consumed first, then the test breads in two fixed, partially balanced sequences. Portions provided 50 g available carbohydrate from manufacturer-declared composition. Capillary glucose was measured at 0, 30, 60, 90, and 120 min; the primary outcome was total incremental area under the curve (iAUC).