Another plus for green tea
New research from Western Australia suggests yet another way green tea is good for your health – preventing a condition mainly experienced by older women.
Above: Professor Andy Lee
By Stephen Easton
Green tea drinkers are significantly less likely to suffer urinary incontinence (UI) than people who drink other beverages like black tea or coffee, according to a study of 298 Japanese women aged between 40 and 75.
The study, recently published in the journal Neurology and Urodyamics, and is the first to have found a link between green tea and urinary incontinence, which is most commonly experienced by older women.
Professor Andy Lee from Curtin University in Perth collaborated with a Japanese team on the study, which found that UI was less common among the women who usually drank green tea than among those who preferred other drinks, and that those who drank four or more cups of green tea per day were significantly less likely to experience the condition.
“We are not asking people with urinary incontinence to drink any extra cups of fluid – of course that may make the condition worse – but because you normally drink coffee, black tea, juice or whatever, perhaps replacing the other beverages with green tea is a good idea,” Professor Lee said.
“Of course this could be related to long term exposure, but on the other hand we must say that it’s never too late. If you haven’t developed the condition already, I think you can still benefit from switching to green tea.”
Previous research suggests that polyphenols found in green tea, particularly one called epigallocatechin gallate (EGCG), are responsible for the ever-growing list of health benefits attributed to it. Most of the polyphenols found in tea, including ECGC, are oxidised during the process used to make black tea.
Other studies in mice have shown ECGC can decrease the occurrence of urinary bladder cancers as well as renal injury caused by high glucose levels, commonly associated with type 1 diabetes.
“In Europe they have undertaken a study to see if black tea has the same effects and they found that it doesn’t, because of the higher caffeine content,” Professor Lee said. “Green tea is known to be a very healthy drink and unlike coffee, it doesn’t have a lot of caffeine. We know that coffee will make urinary incontinence worse; it can induce it.”
Professor Lee has previously worked on studies that have found correlations between the seemingly magical drink and reduced risk of urinary stone formation, prostate cancer, ovarian cancer, lung cancer and ischemic stroke.
He would now like to undertake a much larger study to more thoroughly investigate these latest findings, which were based on looking at data retrospectively.
“This was a relatively small sample of women,” he said. “Basically what we want to do is go out and collect a much bigger sample, collect baseline data and follow them up over time, which is called a prospective study.
“It’s a different way of looking at things. It takes a long time, but we can look at other things, too, like cancer, stroke and all sorts of other chronic diseases.”