Despite what many commercials tout, green tea is not associated with a reduction in cancer risk, experts say. Nor has it been proven that it increases the effectiveness of treatments.
Green tea is becoming more and more trendy and more and more produced in the world. Very rich in epigallocatechin gallate (EGCG), from the catechins family, powerful antioxidants, it would have, if we believe all the commercials, detoxifying properties and incredible drainage. Some even evoke anti-cancer virtues. Yet, according to a report by the World Cancer Research Fund (WCRF) and the American Institute for Cancer Research (AICR), there is no scientific evidence to say that. Moreover, no benefit could be associated with the consumption of green tea during cancer treatments.
Between 2012 and 2018, 24 meta-analyzes were conducted on the subject. And if studies in laboratory animals or cells in culture show that green tea or green tea extracts rich in catechins could reduce the proliferation of tumor cells in high doses, these hypotheses have not been verified. in humans.
On the contrary, it seems that green tea can interfere with certain drug treatments. According to the researchers, it could increase the toxicity of chemotherapy treatments and reduce their effectiveness as well as that of radiotherapy.
Risk of liver toxicity
What's more, green tea decreases iron absorption. It is therefore recommended to drink it outside meals and in limited quantities. If you eat very regularly, prefer green teas from organic farming so as not to expose you to pesticides.
Finally, according to a 2018 opinion issued by the European Food Safety Authority (EFSA) on food supplements based on green tea catechins, a high consumption of green tea (800 mg per day) can lead to risks. of hepatic toxicity. The High Council therefore calls for caution regarding food supplements, especially not to consume without a medical prescription.
Let the tea cool before eating
But green tea has some virtues proven by science. Several researchers have shown that it helps prevent obesity and protect intestinal inflammation. In a recent study published in theJournal of Nutritional Biochemistry, scientists have found that the intestines of mice were better with a diet composed of 2% green tea. Rodents had better gut impermeability and their microbiota was of better quality (bacteria are healthier).
"This study proves that green tea encourages the growth of good intestinal bacteria, which leads to a series of benefits that significantly reduce the risk of obesity," wrote the researchers who would now test this theory on humans.
In France, where coffee and tea account for 28% of drinks consumed by adults after tap water or in bottles (51%), health authorities recommend letting hot beverages cool before ingesting them. Regular consumption of drinks above 65 ° C increases the risk of esophageal cancer.