Background: Type 2 diabetes mellitus is one of the most common health problems. Garlic (Allium sativum) has been the focus of serious clinical attention because of its beneficial effects on the reduction of serum blood glucose. This study was designed to evaluate the effects of garlic on serum glucose level in patients with type 2 diabetes mellitus.

Materials and Methods: This 3-month randomized and double blind clinical trial was conducted on 60 new cases of type 2 diabetes referred to diabetes center of Kashan. The effect of garlic on their blood sugar and HbA1C. was assessed Thirty patients were given 2 tablets of garlic 3 times per day (each tablet containing 400 mg dry garlic powder and over 1000 m g Allicin) and 30 patients (controls) received vitamin B1 tablets. Both groups were given the same diet and exercise programs. Before and after the treatment fasting blood sugar (FBS) and gelycated hemoglobin were measured and analyzed with t-test,

Results: The mean age in the garlic and control groups was 46.3 ± 3 and 45.7 ± 10 years, respectively. There was no significant difference in age, sex, and other diseases between the two groups. After 3 months, the garlic-treated group showed a significant reduction (49.5 mg/dl) in FBS (P<0.001) when compared with the control group. The garlic-treated group also had a significant reduction (1.5%) in gelycated hemoglobin (P<0.003) compared with the control group.

Conclusion: Garlic significantly reduced FBS and HbA1C in type 2 diabetic patients. Hence, it may be a candidate drug in the treatment of diabetes mellitus.