Antidiabetic and Anti-Obesity Effects of Betalains: A Systematic Review of Preclinical Evidence.

Metabolic disorders like diabetes and obesity represent major global health challenges, largely driven by unhealthy dietary patterns and sedentary lifestyles. Growing interest in natural bioactives as complementary strategies is increasing. Betalains, primarily derived from Beta vulgaris, exhibit notable antidiabetic and anti-obesity properties, highlighting their therapeutic potential. This systematic review evaluates the antidiabetic and anti-obesity effects of betalains based on in vitro and in vivo evidence. Literature published between 2015 and 2025 was retrieved from PubMed, ScienceDirect, Scopus, Web of Science, and Google Scholar. Eligible studies assessed betalains effects on glucose and lipid metabolism, while reviews and irrelevant reports were excluded. Out of 508 identified studies, only 12 met the inclusion criteria. The systematic review was registered in PROSPERO under ID 1357942. Risk of bias was assessed using the OHAT tool for in vitro studies and the SYRCLE tool for animal studies. Betalains demonstrated significant metabolic benefits by reducing triglyceride accumulation, fasting blood glucose, insulin resistance, and NF-κB activation, while increasing insulin, adiponectin, and HDL-C levels. They also downregulated total cholesterol, LDL-C, and lipogenic markers (PPARγ, SREBP-1c). Overall, betalains show potential as natural agents against diabetes and obesity; however, well-designed clinical trials with standardized dosing are needed to confirm long-term efficacy.