Please ensure Javascript is enabled for purposes of website accessibility Green Tea Supplements May Cause Liver Damage, Warns EU

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science nutrition <strong>blog</strong>

By Steve Blechman



  The Daily Mail reported on Tuesday, April 18th that the European Union Food Safety Authority (EFSA) ruled that green tea extracts may cause liver damage. The EFSA has evaluated the safety of green tea extract from nutritional sources. According to the Daily Mail, EFSA officials were unable to confirm a safe dose, and the EU watchdog called for “further scientific trials into the effect of green tea catechins and for labels to announce the risks.”

  Catechins are phenolic compounds found in green tea. The most abundant of which is epigallocatechin-gallate-3 (EGCG), which is often present in weight-loss products. Many adverse effects have been reported in the medical journals in recent years. According to the Daily Mail, the EFSA conducted the research amid fears of catechins having “harmful effects on the liver” in England, Norway and other Scandinavian countries.

  Health Canada in November 2017 put forth tougher measures on labels containing green tea extract. Health Canada has ordered a more explicit warning on labels of green tea extract products over concerns about the risk of liver injury. Recently, Health Canada announced it was “clarifying warnings” by asking manufacturers to include the following stronger wording on their product labels:


    "If you have a liver disorder, consult a health care practitioner  prior to use. Stop use if you develop symptoms of liver trouble such as yellowing of the skin/eyes (jaundice), stomach pain, dark urine, sweating, nausea, unusual tiredness and/or loss of appetite and consult a health care practitioner."

    "Rare, unpredictable cases of liver injury associated with green tea extract- containing products have been reported (in Canada and internationally)."


    Between 2013 and 2016, Consumer Reports reported that green tea extract in concentrated form can lead to liver damage, otherwise known as hepatotoxicity. A study by researchers at Wakefield University School of Medicine reported that EGCG is toxic to liver when taken at high doses. The study indicated that 20 cases of liver injury have stemmed from green tea extract supplements. Another study linked green tea extract to liver cancer. In a study of more than 18,000 men, researchers from University of Pittsburgh Cancer Institute found that high levels of EGCG were linked to markers of liver cancer in people who were prone to the disease. The researchers noted that the incidence of liver cancer is much higher in China than in the United States, as green tea is a staple of the Chinese diet.

     With Health Canada and now the EU instituting stiffer guidelines for green tea extract, will the United States follow suit? By taking these steps, Canada and the EU are giving consumers the ability to know that a supplement containing green tea extract could be a potential danger to their health. To recognize the signs of potential liver damage, look for jaundice (yellowing of the skin and eyes). Because of recent studies involving liver toxicity, Health Canada has decided “…as a precautionary measure, product license holders of natural health products containing green tea extract as a medicinal ingredient and are intended for children and adolescents, to either remove the green tea extract from the product or revise the label to indicate that the product is for adults (18 years and older) only.”

     If any of these symptoms appear while you are taking a green tea extract supplement, please go to your nearest emergency room. Be sure to inform the health care professional what supplement you are taking. It could save your life.



    The Daily Mail, April 18, 2018, “Green tea supplements may cause liver damage, warns EU watchdog.”

    Health Canada toughens green tea extract warnings: ‘Cases of liver injury continue to be reported in Canada and worldwide,' safety review says David Common · CBC News · Posted: November 15th 2017, 7:31:44 PM | Last Updated: November 15, 2017

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