Effect of green tea extract on obese women: A
randomized, double-blind, placebo-controlled
Chung-Hua Hsua,b,c, Tung-Hu Tsaid, Yung-Hsi Kaoe, Kung-Chang Hwangf,
Ting-Yu Tsengd, Pesus Choua,b,*
aCommunity Medicine Research Center, National Yang-Ming University, Taipei, Taiwan
bInstitute of Public Health and Department of Public Health, School of Medicine,
National Yang-Ming University, Taipei, Taiwan
cDepartment of Chinese Medicine, Taipei Hospital, Taipei County, Taiwan
dInstitute of Traditional Medicine, National Yang-Ming University, Taipei, Taiwan
eDepartment of Life Science, College of Science, National Central University, Taoyuan County, Taiwan
fDepartment of Pediatrics, Taipei Hospital, Taipei County, Taiwan
Received 25 September 2007; accepted 18 March 2008
Green tea extract;
Aims: To examine the effect of green tea extract (GTE) on obese women and to explore the
relationship between GTE and obesity-related hormone peptides.
Methods: A randomized, double-blind, placebo-controlled clinical trial was conducted from
July 2006 to June 2007 in Taipei Hospital, Taiwan. Seventy-eight of 100 obese women aged be-
tween 16 and 60 years with BMI > 27 kg/m2and who had not received any other weight control
maneuvers within the last 3 months completed this study. The subjects were randomly divided
into Groups A and B. Group A (n Z 41) received GTE while Group B (n Z 37) took cellulose as
a placebo, one capsule (400 mg) three times each day for 12 weeks. The body weight (BW), body
mass index (BMI) and waist circumflex (WC) were measured at the beginning of the study and
after 12 weeks of treatment with GTE. The data were compared and expressed as % reduction.
Results: There was only a 0.3% reduction in BW (0.15 kg) after 12 weeks of treatment with GTE.
There was no statistical difference in % reduction in BW, BMI and WC between the GTE and pla-
cebo groups. Within group comparison revealed that the GTE group had significant reduction in
LDL-cholesterol and triglyceride, and marked increase in the level of HDL-cholesterol, adipo-
nectin and ghrelin. On the other hand, the placebo group showed significant reduction in
* Corresponding author. Community Medicine Research Center and Institute of Public Health, National Yang-Ming University, Taipei,
Taiwan, 155, Li-Nong St, Sec 2, Peitou, Taipei, Taiwan. Tel.: þ886 2 2826 7050; fax: þ886 2 28201461.
E-mail address: firstname.lastname@example.org (P. Chou).
0261-5614/$ - see front matter ª 2008 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.
available at www.sciencedirect.com
Clinical Nutrition (2008) 27, 363e370
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