Effect of Foxtail Millet on Glycemic Response and β-Cell Function in Prediabetes: A Crossover Clinical Study

Prediabetes is a high-risk metabolic stage that demands effective dietary strategies to avoid progression to type 2 diabetes. Millets, especially foxtail millet, have garnered interest for potential glycemic benefits. In this open-label, single-arm crossover study, 14 prediabetic subjects were given foxtail millet foods (25 g available carbohydrates) with and without Ashwagandha and a reference glucose solution. Blood glucose level was assessed at -5 to 120 min, and C-peptide levels were measured at -5, 30, 60, and 120 min. Incremental area under the curve (iAUC), GI, and insulin index (II) were determined. Serum high-sensitivity C-reactive protein (hs-CRP) was measured to evaluate inflammatory response. Safety was monitored throughout the study. Safety was assessed by clinical evaluations. Foxtail millet and foxtail millet with Ashwagandha influenced postprandial glucose levels significantly lower than reference glucose, as well as their iAUC. The GI values were moderate (60.69 and 57.89, respectively), with no significant difference between both test products (p = 0.621). Significantly lower C-peptide responses for both products suggested decreased demand for insulin. Serum hs-CRP levels showed no statistically significant changes, indicating no acute inflammatory response. Both test foods were well tolerated and no adverse events were observed during the study period. Foods based on foxtail millet showed a beneficial glycemic and insulin response at tolerated doses, thereby providing evidence to the existing literature for their possible role in dietary management of prediabetes linked with good safety. The study was registered in Clinical Trials Registry of India (CTRI) (Registration No: CTRI/2025/10/095798 [Registered on: 09/10/2025])