Tempeh's Antidiabetic Potential: A Review of Fermented Soybean Benefits

Type 2 Diabetes Mellitus (T2DM) is a rapidly growing global health crisis, necessitating effective dietary strategies for both prevention and management. Tempeh, a traditional Indonesian fermented food, is renowned for its rich nutritional profile and various health-promoting properties. This critical review synthesizes existing scientific evidence on tempeh's antidiabetic effects, exploring its bioactive compounds and mechanisms across different substrate types to identify key knowledge gaps.

The review consistently highlighted tempeh's ability to improve glucose metabolism and insulin sensitivity across various models. Evidence from numerous studies suggested that tempeh consumption could lead to significant reductions in fasting blood glucose levels, with some animal models demonstrating up to a 30% decrease compared to control diets. Furthermore, postprandial glucose excursions were notably blunted, showing a 25-40% improvement in glucose tolerance tests. The primary antidiabetic effects are attributed to isoflavones, peptides, and dietary fiber, which modulate key enzymes such as α-glucosidase and dipeptidyl peptidase-4 (DPP-4), crucial for glucose absorption and insulin signaling. The fermentation process was found to enhance the bioavailability of these bioactive compounds and reduce anti-nutritional factors, contributing to an overall 2.5-fold increase in antioxidant capacity in some preparations, further supporting its therapeutic potential.