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Green Tea Supplements and Drinks
How Hot Should Green Tea Be? -- (11/25/2017) Drinking green tea may reduce the risk of certain cancers, but its effect on gastric (stomach) cancer may depend on the temperature at which you drink it, according to a new study. Find out what the best temperature seems to be in the "What It Does" section of the Green Tea Review >> (Also see how brands of green tea, including matcha, stack up in our tests.)
How Much Tea Is Safe? -- (11/14/2017) Green and black teas contain fluoride, which helps build teeth and bones, but excessive intake of teas can cause teeth and bones to become brittle ("fluorosis"). How many cups of tea are safe? Find out now based on recent tests of fluoride in green, black, and herbal teas in the "Concerns and Cautions" section of the Green Tea Review >>
Green Tea & Prostate Cancer -- (10/6/2017) A recent study investigated the effects of green tea extract in men with pre-cancerous changes of the prostate. Find out if it helped in the "What It Does" section of the Green Tea Supplements and Drinks Review >>
Tea Drinking Associated with Less Cognitive Decline -- (3/18/2017) A new study found tea drinkers to have significantly less cognitive decline than others. Read the details in the "What It Does" section of the Green Tea Supplements Review (which includes our tests of teas) >>
Colon Polyps and Green Tea -- (2/7/2017) A study of middle-aged men and women found that those given green tea extract after colon polyp removal were much less likely to develop additional polyps than those who did not take the extract. For details about the extract and dose, see the "What It Does" section of the Green Tea Supplements Review (which includes our tests of supplements and teas) >>
Lower Risk of Death With Green Tea -- (7/6/2016) A long-term study of men in China found that those who regularly drank green tea — particularly larger amounts — were less likely to die during the study and had lower risks of dying from cardiovascular disease or cancer, compared to non-green tea drinkers. Get the details in the "What It Does" section of the Green Tea Review >>
Green Tea & Cognition -- (6/18/2016) Green tea consumption has been associated with a lower prevalence of cognitive impairment in older adults. However, a recent study evaluating the effects of a green tea powder on older adults with Alzheimer’s disease and other forms of dementia failed to show a benefit. For more information, see the "What It Does" section of the Green Tea Review >>
Don't Take Green Tea With Iron? -- (3/16/2016) A study shows that iron can bind to a key flavanol (EGCG) in green tea, causing it to lose its anti-oxidant activity. Should you avoid iron-containing foods when using green tea? Find out in the "What to Consider When Using" section of the Green Tea Supplements and Teas Review >>
Are Green Tea Pills Safe? -- (8/25/2015) Studies have suggested that extracts of green tea can reduce the risk of certain cancers, improve memory, shrink uterine fibroids, and even help with weight reduction. However, liver toxicity has been a concern with green tea extracts. A large, government-funded study recently found that pills of green tea extract can be safe for many people, but some may experience adverse reactions, including elevated liver enzymes. Get the details in the "Concerns and Cautions" section of the Green Tea Review, along with information about what green tea does and our tests of green tea extracts, brewable teas, and beverages >>
Green Tea May Inhibit Starch Absorption -- (8/9/2015) A study recently found that taking a green tea extract along with a starchy meal (corn flakes) significantly reduced carbohydrate absorption. This may help explain why green tea may help modestly with weight management. Details about this study, including dosage, along with our tests of green tea supplements and teas, are found in the Green Tea Review »
Green Tea for Weight Management? -- (7/11/2015) Green tea has been touted for weight management, but a recent study with a green tea extract casts doubt. More details are found in the "What It Does" section of the Green Tea Review >>
Green Tea for Weight Control? -- (6/3/2015) Many studies have looked at whether green tea can help with weight management. The results have been mixed. A recently published study used a high-dose green tea extract. Although the researchers concluded it worked, a closer look suggests otherwise, and points to a potential risk. For details, as well as the results of our tests of green tea supplements, beverages, and brewable green tea, see the Green Tea Review >>
Green Tea Extract and Prostate Cancer -- (4/22/2015) A new study, funded by the National Institutes of Health, showed that fewer men with pre-cancerous lesions developed prostate cancer if given a daily green tea extract supplement, although the results were not statistically significant due, in part, to the small size of the study. However, a somewhat similar study found a significant benefit. Learn more about these studies, and see our test results for green tea supplements, teas, and drinks, in the Green Tea Review >>
Another Use for Green Tea? -- (1/16/2015) A recently published study found that rinsing with green tea reduced plaque-forming bacteria in the mouth just as well as a prescription mouthwash. Get the details, including the form and dose of green tea used, in the Green Tea Supplements, Drinks and Brewable Teas Review >>   
Green Tea and Liver Toxicity -- (6/20/2014) Green tea extract was listed as one of the most common dietary supplements linked to liver injury in a newly published guideline for diagnosing and treating drug-induced liver injury. Find out what one of the authors of the guideline had to say about the catechin content of some green tea supplements, and get our test results showing the amounts of catechins in green tea supplements in the Green Tea Supplements, Drinks and Brewable Teas Review >>   
Does Green Tea Really Help With Weight? -- (6/18/2014) A new study found that a popular green tea extract did not cause a reduction in weight compared to placebo, despite the fact that some previous studies have shown a benefit. Get more details, including which green tea extract was used, in the update to the Green Tea Supplements, Drinks and Teas Review >>   
Does Green Tea Improve Memory? -- (4/13/2014) This week, news sources reported that a study found green tea helps working memory. While green tea may have benefits, a closer look at this study suggests the news was exaggerated and misleading. For details about the study (and information about other effects of green tea and our tests of green tea supplements, teas, and drinks) see the update in the Green Tea Supplements, Drinks and Teas Review >> 
Green Tea "Blocks" Beta-Blocker -- (1/18/2014) A new study shows that drinking green tea can drastically reduce the amount of a beta-blocker (nadolol, Corgard) absorbed into the bloodstream. Beta-blockers are typically taken to lower blood pressure, raising concern for people using green tea along with this beta-blocker and, possibly, related medications. Get the details, along with our tests of green tea drinks and supplements, in the update to the Green Tea Review >>   

If you take a beta-blocker (which includes the popular drugs metoprolol (Lopressor, Toprol) and propranolol (Inderal)), be aware that chromium and CoQ10 may offer benefits. These interactions are explained in the Beta Blockers article, which is part of the extensive Drug Interactions section of our website (where you can look up interaction for other drugs you may be taking). 
Liver Toxicity with Supplements, Including Green Tea -- (12/23/2013) An increase in cases of liver toxicity associated with dietary supplement use has recently been reported. In an article about the findings, The New York Times reports that bodybuilding supplements and products containing green tea extracts are among those associated with such cases. For more information about green tea extracts and toxicity, see the Concerns and Cautions section of the Green Tea Supplements Review >> 
Green Tea to Treat Fibroids -- (9/28/2013) A new study suggests that green tea extract may help shrink uterine fibroids (common in women of childbearing age) and reduce symptoms. For details, as well as test results and comparisons of green tea extracts and brewable teas and drinks, see the updated Green Tea Review >>
Don't Drink Too Much Tea! -- (6/2/2013) After publication of our Green Tea Review last month, a CL member emailed us about the potential danger of getting too much fluoride from tea. Although this won't happen from just a few cups of tea daily, there have been recent cases where habitually drinking extremely large amounts of tea has caused "fluorosis" causing bone pain and even tooth loss. See the warning (and our tests of green tea products) in the updated Green Tea Review >>



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