Aim of the paper: To present a systematic review of the scientific literature on the hypoglycaemic effects of garlic (Allium sativum L.), with a focus on its mechanisms of action, clinical efficiency, and potential adverse effects. Materials and methods: Publications from 2015 to 2024 available in the PubMed, Scopus, and Web of Science databases were analysed. These included randomised clinical trials, meta-analyses, and systematic reviews. Results: The collected data suggest that garlic supplementation, particularly in its natural form, can significantly reduce fasting blood glucose levels, with more pronounced effects observed over longer intervention periods. Some studies also report positive effects on glycated haemoglobin, postprandial glucose, and fructosamine levels. The proposed mechanisms of action include increased insulin secretion, improved tissue sensitivity to insulin, and modulation of oxidative and inflammatory processes. Conclusions: The evidence indicates that garlic has considerable potential as a natural adjunct in the prevention and treatment of metabolic disorders. However, further large-scale clinical trials are required to conclusively confirm its efficacy and safety.