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Fev 18, 2012, 6:58 am

Last week I caught part of a BBC TV show - regrettably dumbed down and trivial as much TV is these days - in which they did a short test to measure flavonoids (the salutary antioxidants in tea) as a function of how long the tea was allowed to steep. A range of one minute to seven minutes was examined, I recall, but with no information on the tea used. I presume it was some 'English' breakfast-type blend. The measurements showed that flavonoid yield was greatest at the longest time examined, although most people would object to the bitter taste of such a product.

So I suppose we can deduce that if we seek the health-promoting side of tea, we leave the leaves (!) as long as we can handle from a taste point of view. {I did use the word 'trivial', remember}

So many unanswered questions, even apart from the tea type. I use the same tea leaves, in a spring-loaded wire mesh container for up to half-a-dozen mugs, i.e. until the taste goes. Is this the best way of getting all of the healthy stuff out of them?

Does anyone know of a scientifically based study, with results published?

Fev 18, 2012, 10:19 am

There has been little positive evidence that flavonoids (whatever the source) have that much effect in vivo. Certainly not the same effect that has been shown in vitro.

As for reusing the same tea leaves over and over again. You are likely to be extracting more flavonoids per gram of leaves than if you just used them for one or two cups. However I don't think that should be a factor in your decision making. You are likely (although I haven't done any experiments) to get more flavonoids in your cup of tea if you use fresh tea leaves every time (or at least every other time).

In the end it will be a matter of taste. I couldn't imagine what you must be drinking towards the end of your cycle of brews.

Editado: Fev 18, 2012, 7:33 pm

Generally, the tannins, which cause the bitterness in tea, will begin to be extracted from the tea leaves after 5-6 minutes in boiling water. Hence the common recommendation for a 4-5 minute brew time. I find 3-4 more to my liking; 2-3 for some black blends.

I'm not sure, but it's possible that trying to brew a second cup from the same leaves will then extract the tannins, but I can't say for sure. I don't try to steep leaves a second time.

Along these lines, I highly recommend Malachi McCormick's A Decent Cup of Tea, or his later How to Make a Decent Cup of Tea, which is a small pamphlet extracted from the former.


P.S. - McCormick's Stone Street Press website is worth a peek. Handmade and many using a beautiful calligraphy of his own design. (no financial interest, etc., etc. I just like these small, handmade works. You'll see several in my library.

edited to add the P.S.

Abr 14, 2012, 12:30 pm

I've studied this a fair amount. A lot of people, when it comes to health topics, get stuck in the simple "good vs. bad" mentality, when moderation is really the way to go.

Flavonoids and antioxidants are like this. The antioxidants in tea show evidence of both helpful and harmful effects on the body. As an example, the chemicals in black tea can bind to iron, inhibiting iron absorption. But the chemicals that bind to iron in this way are the same antioxidants that are responsible for some of tea's positive effects on the body.

Some people think the "tannins" in tea are "bad" and the antioxidants or flavonoids (which in black tea are theaflavins and other thearubigins) are "good". But the tannins ARE the flavonoids.

I think in general, it's good to trust both taste and culture. If something tastes bad, it's often a sign it's a bit too much, harsh on the body. And I think it's best to eat or drink things in quantities that cultures normally consume them, not in excess.

Abr 18, 2012, 3:56 am

It's just occurred to me that there's probably a doctorate in it for somebody making a thorough study of why our society is currently so obsessed with individual items of food and drink being good or bad for you.

You can probably pick any item at random and find argument about it somewhere or other. And I'd bet the vast majority of the arguments are based on gross exaggerations of the actual scientific info. Like the carcinogens that are almost certainly going to kill you - if you eat half your body-weight of them every day for a hundred years.

I heard a really ridiculous one lately: would you believe that there are some people who actually believe there are health-benefits from drinking something as inert and neutral as water?!

Abr 18, 2012, 5:48 pm

>5 alaudacorax:
On the other side is the safety people feel about consuming what's 'natural'. Arsenic is natural! Being natural says nothing about potential health and/or environmental effects (good or bad). And many naturally occurring, 'organic' (another of those words) substances can kill.

As my grandmother used to say "Too much of anything is a dog's mess". (Did I already post this quote on this group?)


Jun 29, 2012, 7:38 am


What the body needs is water. People in the West have only been drinking tea for just about 200 years.

Many people will drink anything but water. I have heard many people say that they think drinking warm water is disgusting. They clearly have no idea.

Chinese people will commend drinking tea, but will also say that drinking warm water is actually better than drinking tea.

The experience of drinking warm water (at about the same temperature as tea) is actually very soothing.

I drink black tea the way I drink green tea (but at different temperatures). I will put six to eight grams of black tea in a small tea pot and steep less than 30 seconds; but repeat this four of five times. That amount of tea leaves enables me to make about one litre of tea.

I would not think too much about the health benefits. Drink what you like the way you like it, seems more important to me.

Jul 4, 2012, 6:39 am

As we've strayed into water from the tea which is only fractionally different, perhaps I could add that the ability to heat water is almost essential for camping in our temperate climes. Nothing tastes quite so wonderful after a night in the open than a hot drink, even without the infusion of caffeine-carrying substances such as tea and coffee. I have a feeling that this may be one of the principal features relating to the human discovery of fire.