Influence of Certain Natural Bioactive Compounds on Glycemic Control: A Narrative Review

Glycemic control disorders, including insulin resistance (IR) and type 2 diabetes (T2D), represent a major global health challenge. Although existing therapeutic strategies demonstrate effectiveness regarding glycemic control and reduction in diabetes-associated mortality, they are often associated with limited patient tolerance and adherence. Consequently, there is growing interest in natural bioactive compounds that may support glycemic regulation while potentially posing a lower risk of adverse effects in ongoing therapy. The objective of this review is to evaluate the potential of selected natural substances in the context of blood glucose regulation. The analysis encompasses data from in vitro, in vivo, and clinical studies on compounds such as mannoheptulose, β-carotene, resveratrol, steviol glycosides, and curcumin. These agents have demonstrated the ability to modulate key metabolic pathways, enhance tissue insulin sensitivity, reduce oxidative stress, and support pancreatic β-cell function. Particularly promising effects have been observed when some of these compounds are combined with conventional antidiabetic medications, such as metformin. The review also highlights relevant molecular mechanisms, including activation of the AMP-activated protein kinase (AMPK) pathway, increased expression of glucose transporter type 4 (GLUT4), and modulation of gene expression related to insulin sensitivity. Despite encouraging findings, further clinical research is necessary to determine optimal dosages, therapeutic protocols, and the long-term safety of these substances in human populations. Natural bioactive compounds may thus represent a valuable adjunct to current strategies for managing glycemic disorders.