search for


Clinical Information on Green Tea Extract Used for Weight Loss
Korean J Clin Pharm 2018;28(4):342-346
Published online December 31, 2018
© 2018 Korean College of Clinical Pharmacy.

Youngjin Youn1, Sangyoon Shin2, Kyeong Hye Jeong1*, Euni Lee2*

1College of Pharmacy, Chung-Ang University, Seoul 06974, Republic of Korea
2College of Pharmacy & Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 08826, Republic of Korea
Correspondence to: Kyeong Hye Jeong, College of Pharmacy, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul 06974, Republic of Korea Tel: +82-2-820-6952, Fax: +82-2-816-7338 E-mail:
Co-correspondence to: Euni Lee, Seoul National University College of Pharmacy, Gwanak-ro 1, Gwanak-gu, Seoul 08826, Republic of Korea Tel: +82-2-740-8588, Fax: +82-2-880-9122 E-mail:
Received November 6, 2018; Revised December 17, 2018; Accepted December 26, 2018.
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License ( which permits unrestricted noncommercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Background: Green tea extracts are approved as nonprescription drug and available as health functional foods, health foods, and beverages. Clinical information on the products is lacking.
Methods: Information about the products on green tea nonprescription drugs was obtained from the website of the Korea Pharmaceutical Information Center. The Naver, i.e., a top ranking online search portal, was used for compiling the list of the health functional food products using key words of 'green tea catechin' on August 23, 2018. The recommended daily dosages of catechins were calculated as 30% of the total dried mass of green tea and about 50% of the catechins were considered as epigallocatechin gallate (EGCG).
Results: A total of two types of nonprescription drugs containing green tea powder or extracts, nine health functional food products, and three types of health foods were found. The regulatory requirements of the EGCG exceeding 800 mg were reported to be associated with adverse effects of elevated liver enzyme. If consumers take several green tea products concurrently, such as nonprescription drugs with health functional foods or health foods, it could exceed the recommended amount of EGCG.
Conclusion: The concurrent use of green tea products as nonprescription drugs, health functional foods, and healthy foods may lead to an increased exposure to EGCG. Pharmacists should be aware the availability of various types of green tea products and the potential risk of liver toxicity due to excessive consumption of EGCG.
Keywords : Green tea extract, catechin, EGCG, safety

December 2018, 28 (4)
Full Text(PDF) Free

Social Network Service

Cited By Articles
  • CrossRef (0)

Funding Information