A Review of Clinical Trial Studies on Medicinal Plants in the Treatment of Diabetes

Objective: The use of medicinal plants in diabetic patients is rising, it is essential to increase knowledge about the effects of medicinal plants and subsequently perform evidence-based action, so, review studies are a helpful way for the present purpose. Current study was conducted to investigate the clinical trials of medicinal plants used in the treatment of diabetes in Iran. Materials and Methods: Articles published online between 2010 - 2020 were googled in Magiran, SID, Scopus, and, Iran Medex with Persian keywords such as “type 2 diabetes”, “medicinal herbs”, “healing herbs” “herbs”, “medicinal plants” and “clinical trial”. The inclusion criteria for articles were conducting in the form of a clinical trial, conducting in Iran, publishing in Persian language and having at least a score of 3 based on the Jadad scale. Results: 20 clinical trial studies were extracted. Five studies were conducted on cinnamon and two studies on cumin and the rest of the plants were examined just in one study. Although some trials showed positive effects of the medicinal plants on reducing fasting blood sugar (FBS) and glycosylated hemoglobin (HbA1c), some others demonstrated that medicinal plants had no effect on important variables in diabetes control. Conclusion: Conclusions about the benefits of plants should be made with caution, safety and efficacy of plants in the treatment of diabetes should be investigated further. It is essential that patients take any herbal supplements under physician’s supervision and after receiving the necessary advice.