Wednesday January 3, 2007 | 6 comments
A study at the University of Minnesota Cancer Center published in the December 2006 issue of the International Journal of Cancer shows that subjects who had high levels of green tea polyphenols in their urine had lower rates of colon cancer. Lower urine polyphenol levels were somewhat protective compared to none at all, but those having the highest levels had up to a 60% less incidence of colon cancer.
This study is consistent with many other studies showing lower cancer incidence in tea drinkers, and underscores the direct relationship between the amount of tea consumed and the decreased risk of cancer. Since tea varies greatly in polyphenol content, it is difficult to pin down the number of cups needed for maximum protection, but this study seems to reinforce that more is better. The conclusions in this study are supported by many test tube studies showing that tea polyphenols slow cancer growth, destroy cancer cells, and prevent the formation of cancer cells. To be definitive, further studies are needed using defined amounts of tea polyphenols in tea beverage or in capsules, but this study is very encouraging, and certainly adds to the many good reasons for drinking tea.
“Since tea varies greatly in polyphenol content, it is difficult to pin down the number of cups needed for maximum protection, but this study seems to reinforce that more is better.”
I’d have to respectfully disagree with this opinion in general, though I wouldn’t disagree with it in specific regards to colon cancer prevention. I’m sure there comes a point when too much of a good thing is bad for you.
In general, Phyll, I would have to agree with you. As a clinical herbalist I have become acutely aware, in this country at least, of the mindset that if a little is good for you, then a lot must be better. People think that because an herbal formula is natural that it can’t be harmful if you take more. Medicinal herbs are powerful medicines that if not taken correctly can do harm, just like taking too many drugs. Just look at herbs like Belladona or Foxglove that have been used as powerful medicines and are equally deadly in their natural state as well.
On the whole though, most herbs that are recommended to take as medicinal tisanes can usually be consumed in fairly large quantities without worry. I believe that at least white and green teas fall into that category. But, hey, even water can be deadly if you consume too much: You can literally drown in it.
I have been serving and selling tea for almost a decade and I have alot of customers who drink green tea all day and all night. What I have witnessed in them is a dramatic change in their health, vitality, energy and outlook on life. How much is too much green tea? I think it will vary from individual to individual. People who are in tune with thier bodies know when enough is enough. Over consumption of green tea keeps people awake at night – it’s pretty cut and dried. Drink less tea and get a better nights sleep. Outside of that, I don’t think you can ‘over cunsume’ too much green tea. I drink 3 to 4 pots of tea a day and not once in the last 10 years has anyone ever guessed my age correctly.
Finally, it’s quality as well and not quantity. Supermarket bagged green teas are useless if you are trying to get a polyphenol hit. Buy high grade loose leaf specialty green tea from loose leaf purveyors and you will only have to consume a few cups a day. Even better drink matcha and you will only need one bowl a day.
Brendan
I agree however regarding the sleep issue, there is a way to avoid insomnia. After 3 p.m. I only resteep my tea. By the second pot, the amount of caffeine is pretty negligable, allowing me to continue to drink into the night. Getting up to pee is a whole other issue!
Regarding matcha, Brendan, do you have any clinical data supporting that? I know intuitively that it makes sense. I asked Dr. Milton Schiffenbauer, one of our guest contributors, to do a preliminary test on some matcha. He was unable to confirm your conclusions. We were both quite surprised and disappointed. I’d love to see some evidence that documents the wonders of matcha.
Hi, I also love to re-steep my tea. With some varieties the 2nd steeping is the best. I’ve read that the caffeine is pretty much gone after the 1st steeping, but does anyone know if the same is true for the polyphenols and other constituents in tea? If it’s all released after the first steeping, I’d certainly consider using fresh leaves instead of resteeping.
Richy
There is more and more informtaion available on the properties in Matcha and what is does to and for the human body. For starters, you have to remember then when you drink matcha you are ingesting the WHOLE leaf and not just an infusion of the leaf.
Secondly, this is no ordinary leaf either. Sure there is ‘powdered green tea’ which could be any low grade sencha ground up, but matcha comes from tencha. Tencha is shade grown, tiny, luminescent green tea leaves that have been de-stemmed and de-veined. What is left is the potent ‘meat’ of the inner leaf which is sun dried, then slowly ground into a very fine powder. Recent studies show that matcha contains a significantly higher percentage of all the well known nutrients and anti-oxidents that are found in regular green tea. On top of this, you are also receiving a beta carotene kick when you consume matcha which you don’t get in a cup or green tea. This comes from the simple fact that you ‘eat’ the leaves when you consume matcha – unlike regular tea drinking where you toss the leaves once spent.
If you want more detailed information of matcha check out this site:
http://products.mercola.com/green-tea/
Matcha is exploding in sales right now in Ontario and people are telling us how great they feel, how much more relaxed they are and how their skin feels softer and more supple (sp?)
Now go try some yourself,
happy sipping,
Brendan