title: Garlic intake lowers fasting blood glucose: meta-analysis of randomized controlled trials.
abstract: Garlic is a common spicy flavouring agent also used for certain therapeutic purposes. Garlic's effects on blood glucose have been the subject of many clinical and animal studies, however, studies reporting hypoglycemic effects of garlic in humans are conflicting. A comprehensive literature search was conducted to identify relevant trials of garlic or garlic extracts on markers of glycemic control [fasting blood glucose (FBG), postprandial glucose (PPG), glycosylated haemoglobin (HbA1c)]. A meta-analysis of the effect of garlic intake on human was done to assess garlic's effectiveness in lowering glucose levels. Two reviewers extracted data from each of the identified studies. Seven eligible randomized controlled trials with 513 subjects were identified. Pooled analyses showed that garlic intake results in a statistically significant lowering in FBG [SMD=-1.67; 95% CI (-2.80, -0.55), p=0.004]. Our pooled analyses did not include PPG control and HbA1c outcomes. Because only 1 study included in the meta-analysis reported PPG variables and only 2 studies reported HbA1c variables. In conclusion, the current meta-analysis showed that the administration of garlic resulted in a significant reduction in FBG concentrations. More trials are needed to investigate the effectiveness of garlic on HbA1c and PPG.
authors.affiliation: Department of Rheumatology, the First Hospital of Lanzhou University, China. Email: chuandazhaotieyun@163.com.
authors.forename: Li-qiong
authors.initials: LQ
authors.lastname: Hou
authors.affiliation: Department of Endocrinology and Metabolism, West China Hospital of Sichuan University, China.
authors.forename: Yun-hui
authors.initials: YH
authors.lastname: Liu
authors.affiliation: Department of Endocrinology and Metabolism, West China Hospital of Sichuan University, China.
authors.forename: Yi-yi
authors.initials: YY
authors.lastname: Zhang
mesh_terms: D001786:Blood Glucose / Q000032:analysis*; D004032:Diet; D005215:Fasting; D005737:Garlic / Q000737:chemistry; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D007004:Hypoglycemic Agents; D019518:Postprandial Period; D016032:Randomized Controlled Trials as Topic
chemical_list: D001786:Blood Glucose; D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents