The pervasiveness of diabetes mellitus (DM) is globally escalating, the disease being a consequence of dietary changes and modernization. Snacks are an essential part of the human diet providing satiety and supply of necessary nutrients. As a result of rising consumer demand, research efforts aim to incorporate multigrain flours into snack products which could significantly improve the nutritional composition while harnessing their health-promoting properties. Amaranth, acha, and pearl millet flours were combined in different ratios following optimization using response surface methodology representing SB1 (90: 5: 5) and SB2 (47.98: 26.68: 25.34) and oat snack bar (SBC) served as control. The nutrient composition, glycemic index (GI), antioxidant properties, microbial safety, and sensory quality of the developed snacks were assessed using standard methods. SB1 and SB2 had high protein and ash contents, even so, the carbohydrate and energy contents were similar to SBC. In addition, snack bar had a good balance of amino acids, contained significant macro and micro elements with a Na/K ratio of <1, and the phytate/mineral molar ratios were below their corresponding critical limits. Multigrain snack bars depicted low GI (42.78, 45.03), especially SB1 while SBC had intermediate GI (62.34). Multigrain snack bar also exhibited significant • OH scavenging ability, Fe 2+ chelation, and the ability to inhibit Fe 2+ -induced lipid peroxidation. SB1 has the highest protein content (21.95%), the composition of essential amino acid exceeds the reference standard, a low GI, and low postprandial blood sugar level (132 mg/dL), thus conceivably may qualify as a healthful dietary snack being nutrient-dense with antioxidant and hypoglycemic properties
