Journal of
Medicinal Plants Research

  • Abbreviation: J. Med. Plants Res.
  • Language: English
  • ISSN: 1996-0875
  • DOI: 10.5897/JMPR
  • Start Year: 2007
  • Published Articles: 3834

Full Length Research Paper

Effects of garlic on blood glucose levels and HbA1c in patients with type 2 diabetes mellitus

Rizwan Ashraf M. Phil1*, Rafeeq Alam Khan1 and Imran Ashraf2
1Department of Pharmacology, Faculty of Pharmacy, University of Karachi, Pakistan. 2Department of Geriatric Medicine, King’s Hospital London, London, UK.
Email: [email protected]

  •  Accepted: 08 April 2011
  •  Published: 04 July 2011


The aim of the present study was to evaluate the effects of garlic on fasting blood sugar and HbA1c in patients with type 2 diabetes mellitus. This was a 24 week, single-blind placebo controlled study. The patients (n = 210) with fasting blood sugar above 126 mg/dl were recruited and divided into 7 groups (A, B, C, D, E, F and G), each comprised of 30 patients. Group A, B, C, D, and E were given garlic tablets at doses of 300, 600, 900, 1200, and 1500 mg per day, respectively. Group F received metformin while group G received placebo. FBS and HbA1c were measured at week 0, 12 and 24. Present study showed significant decrease in fasting blood sugar and HbA1c in both dose and duration dependent manner. In each garlic treated group, significant reduction in FBS (p <0.005) and HbA1c (p <0.005) were observed when compared with placebo. Highly significant reduction in FBS and improvement in HbA1C were observed at higher doses of garlic and with increase in the duration of study. Garlic is more effective than placebo and comparable to metformin in reducing fasting blood glucose and may be a valuable addition in the management of diabetic patients.


Key words: Garlic, diabetes mellitus, fasting blood sugar, HbA1C, complementary therapy.