Combined Supplementation With Trigonella foenum-graecum and Nigella sativa Seed Powders Improves Glycemic Control,...

Diabetes mellitus is characterized by persistent hyperglycemia accompanied by dyslipidemia, oxidative stress, and progressive hepatic, renal, and hematological disturbances. This study evaluated the compositional, antioxidant, and preclinical antidiabetic potential of Trigonella foenum-graecum (fenugreek) and Nigella sativa (black seed) powders, administered individually or combined, in alloxan-induced diabetic rats. Fenugreek powder contained high crude fiber (22.1%) and moderate protein (20.5%), whereas black seed powder showed high crude fat (38.9%) and appreciable protein (20.9%). Total phenolic content was substantially higher in black seed powder (185.3 mg ± 7.6 mg GAE/g) than in fenugreek powder (47.1 mg ± 2.0 mg GAE/g), although both exhibited comparable DPPH radical scavenging activity (63.8%-63.9%). Diabetic rats received fenugreek, black seed, or their combination (100 mg/kg body weight) for 28 days alongside healthy and untreated diabetic controls. All treatments improved glycemic status, with the combined treatment producing the greatest HbA1c reduction (8.9% to 5.1%) compared with fenugreek (6.4%), black seed (6.2%), and untreated diabetic rats (8.1%). Treatments also improved dyslipidemia, hematological indices, and hepatic and renal biomarkers, with the combined treatment consistently showing superior efficacy. These findings support fenugreek and black seed powders as bioactive-rich functional ingredients with complementary glucose-lowering and organ-protective effects, highlighting their promise as a multi-target dietary adjunct against diabetes. PRACTICAL APPLICATIONS: This study demonstrates that the combined use of Trigonella foenum-graecum (fenugreek) and Nigella sativa (black seed) powders has potential as a functional food ingredient or nutraceutical formulation for dietary management of diabetes. Their complementary bioactive composition improved glycemic control, lipid metabolism, and liver and kidney function in a preclinical model, supporting their application in developing value-added functional foods, health supplements, and plant-based therapeutic diets aimed at reducing diabetes-associated metabolic complications.