Foods/Supplements-Vitamins: Green Tea, etc, & Polutants

A. Introduction.

Tea comes from the plant Camellia sinensis. The plants require 50 inches of rain each year. As with any leaf with a high water uptake, there might be a high accumulation of whatever is in the soil.

"Processing of different types of teas is as follows. [B1]

1. White tea: young leaves or new growth buds, withered, uncured, baked dry;

2. Green tea: steamed or dry cooking in hot pans to prevent oxidation;

dried tea leaves may be separate leaves or rolled into pellets (gunpowder tea);

3. Oolong tea: withering of leaves under sun and warm winds

with further oxidation standard between green and black teas;

4. Black tea: leaves are completely oxidized, withered, and disrupted or macerated

to activate oxidation resulting in catechins being transformed to complex tannins."

The catechins (a form of polyphenol) are thought to be the active ingredients - primarily epigallocatechin gallate (EGCG).

B. Is Tea Safe?

If tea is to have any therapeutic value against PCa, it is likely that a significant number of cups would have to be consumed each day. If the tea contains contaminants, there might be unsafe intake & accumulation.

When buying tea grown in China, it may be worth remembering that the country burns half of the world production of coal. However, tea may be grown in soil that naturally contains toxic minerals.

"Tea plants ... grow in acidic soil {which} may result in excess available aluminum and fluoride" [B1]

[B1] Heavy Metals.

There are 100 PubMed hits for <tea "heavy metals"> & I have cherry-picked this one: (2013 - Canada)

"Common off-the-shelf varieties of black, green, white, and oolong teas sold in tea bags were used for analysis in this study. Toxic element testing was performed on 30 different teas by analyzing (i) tea leaves, (ii) tea steeped for 3-4 minutes, and (iii) tea steeped for 15–17 minutes. Results were compared to existing preferred endpoints.

"Results:

"All brewed teas contained lead with 73% of teas brewed for 3 minutes and 83% brewed for 15 minutes having lead levels considered unsafe for consumption during pregnancy and lactation."

("All brewed tea and tea leaves had detectable lead levels with Chinese oolong teas having the highest levels, followed by green tea and regular black tea having lower levels. Organic white teas had the lowest lead level. Levels ranged from 0.1 μgm/L to 4.39 μgm/L after subtracting the level found after brewing distilled water in fine china cups.")

"Aluminum levels were above recommended guidelines in 20% of brewed teas."

("All teas contained significant amounts of aluminum. Tea leaves contained from 568 to 3287 ng/g of tea. All brewed teas steeped for 3 or 15 minutes contained detectable levels of aluminum. The range was 1131 μgm/L to 8324 μgm/L steeping for 3 minute and 1413 μgm/L to 11449 μgm/L steeping for 15 minutes. Only 2 teas had levels above acceptable limits at 3 minutes of brewing but 6 of the teas had levels greater than the upper acceptable daily limit of 7000 μgm/L. Clearly letting tea steep for longer than 3 minutes is not advisable. Two of the organic green teas had levels above 10,000 μgm/L brewed for 15 minutes.")

"No mercury was found at detectable levels in any brewed tea samples."

("although 18/30 tea leaves had detectable mercury present (as high as 20 ng/g of tea). It appears that the mercury is bound in the leaf in a way that it does not make its way into the brewed tea at levels that are detectable")

"All brewed tea and tea leaves had detectable arsenic with Chinese oolong teas (organic or regular) having the highest levels. Levels in all teas ranged from 0.06 μgm to 1.12 μgm/L of tea steeped for 3 minutes to 0.08 to 1.27 μgm/L of tea steeped for 15 minutes."

"All tea leaves had detectable levels of cadmium. 21 teas had detectable levels after 15 minutes brewing while only 18 teas had detectable levels after 3 minutes brewing suggesting that there is further leaching of this toxicant into the water over time. The highest level was 0.067 μgm/L found in standard oolong tea from China."

"All tea leaves and brewed teas had detectable levels of cesium with one organic tea having 3103 ng/g in the dry leaf, 12.4 μgm/L at 3 minutes of brewing and 16.5 μgm/L at 15 minutes of brewing."

"All tea leaves had detectable levels of tin but only two brewed samples had nonsignificant levels detected in the teas."

"All tea leaves and all teas had detectable levels of barium, antimony and thallium but none had levels considered to be of concern."

"Of the trace minerals manganese is the only mineral found in substantial amounts in teas and some teas will supply more than the total daily requirements. Black tea achieved the highest level in this study. Excess manganese can result in interference with the absorption of iron and may result in ADHD-like symptoms in children exposed in utero."

[B2] Fluoride. There are 318 PubMed hits for <tea fluoride>.

See also: "Foods/Supplements-Vitamins: Iodine & other Halides" for the negative effect of fluoride on iodine status.

[B2a] (2008 - Taiwan]

"Lungjing, pouchong, tienguanyin, oolong, pureh, and black tea specimens were purchased from different counties in Taiwan. Fluoride levels were evaluated in one complete cycle of tea making as well as at different calcium carbonate contents in water, with glass or porcelain teapots, and with/without adding sugar."

"Among six kinds of tea, black tea had the highest fluoride concentrations (8.64+/-2.96 mg/l), whereas pureh (1.97+/-2.70 mg/l) had the lowest levels."

"... intakes of high amounts (> or =5 l/week) of certain tea may result in excess risks of dental or skeletal fluorosis." {5 liters = 10.6 US pints, weekly; = four 6 oz cups daily}

[B2b] (2016 - Ireland)

"The Republic of Ireland (RoI) is the only European Country with a mandatory national legislation requiring artificial fluoridation of drinking water and has the highest per capita consumption of black tea in the world. Tea is a hyperaccumulator of fluoride and chronic fluoride intake is associated with multiple negative health outcomes. In this study, fifty four brands of the commercially available black tea bag products were purchased and the fluoride level in tea infusions tested by an ion-selective electrode method. The fluoride content in all brands tested ranged from 1.6 to 6.1 mg/L, with a mean value of 3.3 mg/L. According to our risk assessment it is evident that the general population in the RoI is at a high risk of chronic fluoride exposure and associated adverse health effects based on established reference values. We conclude that the culture of habitual tea drinking in the RoI indicates that the total cumulative dietary fluoride intake in the general population could readily exceed the levels known to cause chronic fluoride intoxication."

(For members in Ireland: Table 2 identifies the 54 brands & fluoride levels.)

[C] Liver Toxicity & Tea Supplements.

The Life Extension green tea product [C1] claims to deliver "more polyphenols than you get from drinking seven cups of green tea". From personal experience, I can say that it may be unwise to take more than one capsule at a time. Keep an eye on liver enzymes.

-Patrick

[B1] ncbi.nlm.nih.gov/pmc/articl...

[B2a] ncbi.nlm.nih.gov/pubmed/174...

[B2b] ncbi.nlm.nih.gov/pmc/articl...

[C1] lifeextension.com/Vitamins-...

9 Replies

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  • Well. There goes the green tea.

  • Things that make you go..hmm.

    Well researched, Patrick!

    Mark

  • Nice Research - Very interesting.

  • Hi Patrick,

    Is there a reason you use LEF's lightly caffeinated green tea instead of their decaffeinated, which is what I use? (There are two more questions at the end of this post.)

    Donald Abrams, the oncologist at UCSF's Osher Center for Integrative Medicine, advised me 10 years ago not to consume more caffeine that there is in 3 cups of green tea. That was also the amount of green tea he wanted me to drink, in addition to my decaf GT extract.

    I switched to white tea when I found out it was even healthier, & it tastes better (no tannin flavor). I'm going to stick with the white tea, even though my wife read that it has more caffeine than green, the opposite of what I expected. So I'm hoping there isn't a good reason to take an extract that has caffeine.

    The best tasting & probably healthiest white tea I've found is Teatulia, available online from Teatulia. I use their white tea, but some might prefer their white tea with peony, or another of their teas. The attractive, see-through teabags are a silken soy derivative.. Teatulia is based in Denver. It's a socially & environmentally conscious company. They grow their teas in Bangladesh, where they hired hundreds of previously unemployed local women to do the work. The teas are USDA-certified organic, & Rainforest Coalition-certified.

    Questions:

    1. In your opinion, are USDA-certified food products grown in soil free of toxic minerals?

    2. Since white tea consists of the youngest leaves & buds, wouldn't they contain less toxic minerals than other teas from the same tree?

    Thanks for this & for all you do for us.

    Neal

  • Hi Neal,

    LEF has stated that a small amount of caffeine helps with the absorption of EGCG, etc. In fact, the "lightly caffeinated" version, while equivalent to 7 cups of tea, has only the caffeine of two-thirds of a cup (25 mg). I have not seen the basis for their claim, however, but that amount of caffeine doesn't worry me.

    I have never come across white tea. Assuming it is the real thing (Camellia sinensis), it should contain far lower levels of toxic minerals. Essentially, the burden is relative to how much water has been taken up, which tranlates to time on the stem.

    I am a transplanted Englishman, so was appalled by the tea situation when I arrived in America in 1974. Particularly galling, was how restaurants would bring hot water for your second cup. There was hardly any flavor in the first cup, yet one was expected to re-use the tea bag.

    When Indian grocery stores began to appear in Manhattan, I would buy tea from them. The name "Lipton" means something quite different in India.

    I like a robust flavor & that means tannins to some degree. I like green tea, but I love black tea. I now prefer coffee, but buy tea for my wife from Mark Wendell in Boston. They carry some white teas:

    marktwendell.com/shop/searc...

    I once worked with a Yorkshire man in England. If it was my turn to make the tea, he would get really annoyed if I did not allow the kettle to get to a rolling boil. As with coffee, tea is best brewed at about 180 degrees, otherwise the tea is bitter. In the north of England, they want boiling water to bring out the full tannins. To a southerner, the tea tastes stewed.

    But the tannins are beneficial polyphenols. I think that black tea studies are disappointing only because a lot of black tea drinkers use milk to neutralize the tannins. Casein binds to them & the benefit is lost.

    I think that the USDA does a poor job in some areas. In terms of being certified as "organic", the concern would be that the land not have been treated with pesticides, etc. The minerals naturally found in the land would be of no concern.

    The FDA could get involved with tea, the way they did with arsenic in rice. From 2005:

    foodnavigator-usa.com/Regul...

    Thanks for the Teatulia heads-up.

    Best, -Patrick

  • Hi Patrick,

    Thanks for a great response! Timely, too. I'm just about to order more of the green tea supplement (I order everything from iHerb.com), & will get the lightly caffeinated.

    I've found a few brands of white tea in supermarkets in Berkeley & Oakland that carry a lot of healthy food. Then one day a Teatulia rep was passing out small cups of their teas in front of one of those stores, Berkeley Bowl (their original store was a former bowling alley), & I tasted the best tea (to my tastebuds) I've ever had. The store doesn't carry it anymore, but I buy it from Teatulia in Denver. It's not cheap, but it's so good, & it's a company worth supporting. I've also had white tea from a tea store. All the white teas have been Camellia sinensis.

    For white tea, I bring the water to a boil, let it cool for 1-2 minutes, & brew it for 2.5-3 minutes. For coffee, I never heard about letting the water cool, so I guess I always did it wrong.

    I was a coffee drinker until my prostatectomy. I was in love with Peet's French Roast. (Peet's started in Berkeley, but I'll bet it's in NYC now.) I was reading that green tea could be beneficial, & I knew I couldn't do both or I'd be in the WC all the time. I reduced my coffee intake by 1/6 each of the 6 days leading to the removal of the catheter, & thereby avoided any withdrawal symptoms. Then I started green tea--& wasn't too happy about it until I found white tea.

    I have been happy about having far less caffeine in my life. I'm on an even keel with no lows, & no racing heartbeat.

    It's also interesting timing that you sent me the article about fluoride in tea. I just saw an anti-fluoride article by Dr. Mercola. What do you think of him? What do you think about fluoridated mouthwashes?

    Best,

    Neal

  • Just read my new email from Dr. Mercola, about evil ingredients in toothpaste, starting with fluoride. For instance, Colgate Total, which my dentist wants me to use at bedtime (I'm otherwise using Biotene for my dry mouth, which has no fluoride), has triclosan, which Mercola says can cause cancers including PC! I think I'll start making my own, following his recipe.

  • Neal,

    The thing about coffee, as with tea, is that boiling water brings bitterness to the cup. Time is an enemy too. With the drip method, the water temperature is OK but by the end of the process, bitter coffee is falling into the pot.

    Espresso machines eliminate the time problem, but introduce the heat issue. The last half of an espresso is terrible stuff. A restretto uses only half the water & is delicious. A double restretto makes up the volume, but of course, uses twice as much coffee. In my coffee post, I mention the AeroPress, which solves the temperature/time issues. It is inexpensive, but entirely manual.

    Dr. Myers has said that Mercola is wrong just about everything. I certainly don't believe that, but I'm wary of anyone who is pushing supplements & casts his net so wide.

    His views on statins are a bit extreme. I think it's a shame that a lot of healthy people take statins - it's a case of tackling the wrong problem. But a man with PCa might come away from his site thinking that a statin is the most dangerous thing he could put inside his body. In fact, cholesterol levels in PCa cells are associated with progression, & cholesterol in those cells can be used to make androgens & get around ADT.

    With fluoride, the thing to remember is that it competes with iodine (just as bromide does). I take Iodoral every day, so ensure a competitive advantage for iodine. I don't know how much of a threat the mouthwashes are, but it is obviously higher in men with poor iodine status.

    -Patrick

  • Thanks very much, Patrick. This is very useful.

    What I've read about statins (I was already on 1 before my dx) & PCa suggests that they're a useful part of our PCa-fighting arsenal.

    I looked in a hip pharmacy (Pharmaca) today for Iodoral, without luck, but I bet I'll find it on iHerb now. I know they have the lightly caffeinated LEF GT extract.

    Neal