Research Article: Changes of Insulin Resistance and Adipokines Following Supplementation with Glycyrrhiza Glabra L. Extract in Combination with a Low-Calorie Diet in Overweight and Obese Subjects: a Randomized Double Blind Clinical Trial

Date Published: March 18, 2018

Publisher: Tabriz University of Medical Sciences

Author(s): Mohammad Alizadeh, Nazli Namazi, Elham Mirtaheri, Nafiseh Sargheini, Sorayya Kheirouri.


Purpose: Adipose tissue is a highly active endocrine organ which plays a key role in energy homeostasis. The aim of this study was to determine the effects of dried licorice extract along with a calorie restricted diet on body composition, insulin resistance and adipokines in overweight and obese subjects.

Partial Text

Adipose tissue is a highly active endocrine organ, which plays a key role in energy homeostasis, response to hormonal signals, metabolic regulation and adipokine secretion.1 Current evidence suggests that adipose tissue secrets more than 50 signaling molecules and hormones, called adipokines.1,2Adipokines are involved in the regulation of thermogenesis, appetite, glucose metabolism, insulin sensitivity and other endocrine functions.3 One adipokine is vaspin, a visceral adipose tissue-derived hormone which can be considered to be a new link between obesity and metabolic complications such as insulin resistance, type 2 diabetes and atherosclerosis.4 Several studies have indicated an association between vaspin and body mass index (BMI); but the findings are contradictory. 5

As presented in Figure 1, of the 64 participants, 58 subjects completed the study (intervention group, n=29; placebo group, n=29). The power of the study at the end of the study was 85%. Participants did not report any serious side effects for taking licorice supplement, except one who reported gastrointestinal problems and discontinued the study.

The present study highlights that licorice extract supplementation concurrently with a low-calorie diet, sufficiently attenuates serum levels of vaspin hormone in overweight and obese subjects with no significant side effects. The findings also revealed that a low-calorie while taking licorice supplementation was no more efficacious than a low-calorie diet alone on the management of obesity.

We conclude that supplementation with dried licorice extract plus a low-calorie diet can increase vaspin levels in obese subjects, with no changes in insulin resistance and body composition. Overall, the effects of the intervention was not stronger than a low-calorie diet alone in the management of obesity.

We are grateful to the participants for their cooperation. The authors also would like to thank the Nutrition Research Center, Tabriz University of Medical Sciences for funding the project.

The trial was approved by the Ethics Committee of Tabriz University of Medical Sciences and written informed consent was obtained from each patient. The trial was registered on the Iranian registry of clinical trials (, IRCT2013062811288N3).

Authors declare no conflicts of interest




Leave a Reply

Your email address will not be published.