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The catechins in green tea act like sports trainers for individual cells that initially undergo oxidative stress but soon develop the ability to defend against attack by free-acid radicals.
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The catechins in green tea act like sports trainers for individual cells that initially undergo oxidative stress but soon develop the ability to defend against attack by free-acid radicals.
Green tea catechins are not passive antioxidants but pro-oxidants that act in ways like a vaccination that strengthens cells against attack by free radicals.
Ingesting green tea polyphenols holds outsized benefits because a diet rich in antioxidants is associated with delays in aging and offers one of the most effective treatments for high blood pressure. According to researchers, three cups daily lead to a significant reduction in systolic blood pressure and fasting glucose as well as weight loss in type 2 diabetes patients,
The mechanism by which tea counteracts or prevents oxidative stress is not well understood but is associated with a cluster of catechins. Epigallocatechin gallate (EGCG) is the most abundant. Researchers assumed the benefit was defensive, shielding individual cells from harm. A new study in the journal Aging revealed a surprising capability of green tea catechins not only to neutralize harmful free radicals but to improve the capabilities of the cells of laboratory organisms, leading to longer life and greater fitness.
“That means green tea polyphenols, or catechins, aren’t in fact antioxidants, but rather pro-oxidants that improve the organism’s ability to defend itself, similar to a vaccination,” study leader Michael Ristow, professor of energy metabolism at the health sciences and technology department at ETH Zurich told Futurity in an article titled: Green Tea Discovery Upends Ideas About its Health Benefits.
The article, posted by Peter Ruegg at ETH Zurich, explains that, unlike vaccines that stimulate the immune system, green tea activates genes that produce certain enzymes such as superoxide dismutase (SOD) and catalase (CTL) that deactivate free radicals in nematodes, the test organisms chosen for the study. Initially, the presence of the catechins increases oxidative stress for a short while which has the subsequent effect of increasing the defensive capabilities of the cells and the organism, writes Ruegg.
The findings from the study translate well to humans, said Ristow. “The basic biochemical processes by which organisms neutralize oxygen free radicals are conserved in the evolutional history and are present in everything from unicellular yeast to humans,” he said. Ristow, a green tea drinker himself, said catechins are more plentiful in green tea than black because polyphenols are largely destroyed by the fermentation process.
The UK Tea Advisory Panel endorses the consumption of moderate amounts of green tea, citing a meta-analysis of 24 health studies involving 1,697 patients. “EGCG, the dominant phenolic compound in green tea, boosts nitric oxide levels which lowers blood pressure,” the panel Tweeted.
Globally, about 30% of adults suffer from hypertension, which is the main risk factor for cardiovascular disease as well as early death. In the US hypertension [systolic BP greater than 130 mmHg] affects 47% of adults and contributes to the cause of one in six deaths.