Green Tea Health Benefits: Is There Proof?

[misskitty]

has science found any documented proof that drinking green tea every day has health benefits for you? If so what are they?

~Kitty

 

[arildno]

Guy de Maupassant wrote a chilling ghost-story called "Green Tea".
Apart from that, I don't know anything about green tea.

(Sorry for being facetious, misskitty, but I loved the story so much when I read it years ago. Wonder if it is still as good..?

 

[misskitty]

Its ok. I don't mind. If you can't laugh in life what good is living?

~Kitty

 

[hitssquad]

has science found any documented proof that drinking green tea every day has health benefits for you?

lef.org/magazine/mag99/mag99_6.html

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Green Tea Part 1:
Anti-carcinogenic properties of green tea

Green Tea Part 2:
Good for the Soul but even better, Good for the Heart
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ncbi.nlm.nih.gov/entrez/query.fcgi?CMD=search&DB=PubMed&term=egcg

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[hitssquad]

ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=15629234

Epidemiological studies have indicated that regular consumption of red wine and green tea is associated with a reduced risk of coronary heart disease and tumor progression. The development of tumors and of atherosclerosis lesions to advanced plaques, which are prone to rupture, is accelerated by the formation of new blood vessels. These new blood vessels provide oxygen and nutrients to neighboring cells. Therefore, recent studies have examined whether red wine polyphenolic compounds (RWPCs) and green tea polyphenols (GTPs) have antiangiogenic properties. In vitro investigations have indicated that RWPCs and GTPs are able to inhibit several key events of the angiogenic process such as proliferation and migration of endothelial cells and vascular smooth muscle cells and the expression of two major proangiogenic factors, vascular endothelial growth factor (VEGF) and matrix metalloproteinase-2, by both redox-sensitive and redox-insensitive mechanisms. Antiangiogenic properties of polyphenols have also been observed in the chick embryo chorioallantoic membrane since the local application of RWPCs and GTPs strongly inhibited the formation of new blood vessels. Moreover, intake of resveratrol or green tea has been shown to reduce corneal neovascularization induced by proangiogenic factors such as VEGF and fibroblast growth factor in mice. The ability of RWPCs and GTPs to prevent the formation of new blood vessels contributes, at least in part, to explain their beneficial effect on coronary heart disease and cancer.

 

[misskitty]

Wow. I guess it is a good thing I drink green tea then. Does anyone care to speculate as to the motivations for such extensive research on this tea?

~Kitty

 

[quetzalcoatl9]

Wow. I guess it is a good thing I drink green tea then. Does anyone care to speculate as to the motivations for such extensive research on this tea?

~Kitty

there is a lot of money in researching natural products for the treatment of disease, especially cancer and heart disease. it isn't too hard to get a grant from NIH or AHA to HPLC natural products and then test them in cell culture - in fact there is a lab at NIH that can screen compounds against hundreds of cell lines for a hefty fee.

from a research perspective, it can also be quite fruitful since nature has done all of the hard work in making the natural products. (i know someone working in this area right now, who has an anticancer drug - isolated from a marine organism - in clinical trials).

resveratrol (from red wine) was at one time considered a potential life-extending drug - i don't know if further studies have validated that.

 

[misskitty]

I do know that the componates of red wine are good for your heart and something else. I can't recall off the top of my head.

It only makes sense there should be a natural way to cure these diseases. After all, nature did create them. It made an antidote somewhere.

~Kitty

 

[Kerrie]

good to know! i drink green tea regularly, and red wine frequently (when i am unpregnant of course), so my family tendency of heart disease can be possibly counteracted with these two great drinks.

 

[misskitty]

This is very true. Luckily my fiance has a thing for red wine. He also has a long family history of heart disease. Perhaps green tea in the morning and a glass of red wine with dinner have similar benefits for him.

Good to hear from you Kerrie. I haven't talked with you in a while.

~Kitty

 

[iansmith]

I like to point out that drinking does not mean good protection. I remember seen this report on discovery that soaking time had a major influence on the release of the protective agent. If I remember correctly, soaking of less than 2 minutes had a minimal effect.

This is not the report in question but it does demonstratred the point.
http://www.ncbi.nlm.nih.gov/entrez/...d&dopt=Abstract&list_uids=10817628&query_hl=1

I also found this.
http://www.exn.ca/Stories/2003/11/06/54.asp

 

[hitssquad]

I remember seen this report on discovery that soaking time had a major influence on the release of the protective agent.

No problem. I used to just eat the leaves. Now I take it in pills. Another option I have used: BAC has extracts of green tea in inexpensive powder form.
easycart.net/BeyondACenturyInc./Herbals_F-J.html#8290

 

[misskitty]

That is true you can get the effects of green tea in different forms. Hitssquad how did those leaves taste? Good thing I like me tea strong an leave the bag in the tea for at least 6 minutes.

~Kitty

 

[selfAdjoint]

I don't have a history of heart trouble but I do take medication for blood pressure, and I have a cuff for daily monitoring at home. I had been in the habit of drinking two cups of Earl Grey tea each afternoon, but on an occasion I switched to green tea. I always let it brew 5 minutes. I find that when I drink green tea my BP goes down, but when I go back to regular tea it goes up. Whether this is due to the caffeine in the regular tea constricting my blood vessels or due to something positive in the green tea I don't know.

Now I'm going to share something controversial. When I had my checkup last month my LDL cholesterol was excellent, and my HDL was just barely in the acceptible region. So, desiring to raise my HDL if possible, I went online. And I found that good things for raising HDL are the things you do to lower LDL; excercise, long walks, lean low salt diet. I do all those things. But I found one thing specifically for HDL that the sites were almost embarrassed to mention, though it's an established effect; a shot of whisky every day is good for HDL. For me it's more like every few days, because I don't want to establish a dependency. But it's now a part of my life style.

 

[misskitty]

Wait isn't LDL 'good cholesterol' and HDL is 'bad cholesterol'? So when you say your HDL was "barley in the acceptible region" did you mean it was too low?

Wouldn't you want it low? Or do I have that backwards?

~Kitty

 

[misskitty]

I find when I feel a cold coming on if I drink 5-6 servings of green tea that I feel better the next day. Could that be attributed to the antioxidents in the tea? I don't know of any other teas that work the way green tea does. Does anyone know of a tea with similar effects to green tea?

~Kitty

 

[iansmith]

Wait isn't LDL 'good cholesterol' and HDL is 'bad cholesterol'? So when you say your HDL was "barley in the acceptible region" did you mean it was too low?

Wouldn't you want it low? Or do I have that backwards?

~Kitty

LDL is the bad and HDL is the good.

 

[misskitty]

Guess I did get them confused (again.) Sorry.

~Kitty

 

[hitssquad]

How to remember the differences between HDL and LDL

Guess I did get them confused (again.)

You might relate them to bodyfat and muscle. Muscle is generally preferable to bodyfat and is heavier (high density). HDL is generally preferable to LDL and is heavier (High Density Lipoprotein).

In fact, HDL is "a lipoprotein of blood plasma that is composed of a high proportion of protein with little triglyceride and cholesterol." HDL is heavier (high density) precisely because it has more protein and less fat and cholesterol than LDL.

 

[misskitty]

Huh, thanks Hitssquad. So the green tea is good at lowering the LDL?

~Kitty

 

[hitssquad]

Levels of cholesterol vs oxidation of cholesterol

As far as I am aware, cholesterol levels are irrelevant to cardiovascular health. Green tea inhibits oxidation, which is important for cardio health, of both HDL and LDL and in fact LDL may have positive health impacts (as long as it is not oxidized). Fish oils are toxic if they are oxidized, yet they are beneficial to health if they are not oxidized. Perhaps high LDL levels became associated with cardio disease because the LDL in the persons measured tended to be oxidized and therefore toxic.

Your brain is composed of LDL, by the way. Reduce LDL and you suffer diseases of demyelination including adult-onset mental-retardation. Completely remove LDL from your body and you die.

HDL, on the other hand (being more protein and less lipid), is harder to oxidize. Therefore it gets the label from journalistic (and not scientific) medicine of "good cholesterol," though it may in fact be quite harmful to raise it in comparison with the possibly much-more-important-for-health LDL.

 

[champ2823]

I find when I feel a cold coming on if I drink 5-6 servings of green tea that I feel better the next day. Could that be attributed to the antioxidents in the tea? I don't know of any other teas that work the way green tea does. Does anyone know of a tea with similar effects to green tea?

~Kitty

I drink green tea as well. Actually to think about it I only drink teas, iced teas, water, and alcohol. No sodas for me. When I feel like I'm getting sick I take Echinacea and I already have a high Vitamin C intake daily and have found that I haven't been sick in a couple years.
Another thing with Green Tea is that it is an alkalizer and Nobel Peace Prize winners have done research on the affects of PH balance in your body. When I had my aquariums set up, ph was a big issue as if it got too high or low, my fish would be on their way down the toilet. Likewise, our body has a normal ph level beween 7.0 and 7.3 or closely similar dependent on the source. Anyways, these scientists as well as many scientists and doctors today have done research on ph levels relevant to people who are sick with just about anything like influenza, cancer, etc. Their findings conclude that cancer patients, etc., almost always have an abnormally low acidic ph. By raising the ph level of those people to alkaline, it has resulted in the cancer going away. The results are pretty mind boggling but this practice isn't really done in the U.S. where chemotherapy is primarily used with little proven results...but it's very expensive. In Europe, the ph thing is growing rapidly in popularity. It's really an interesting subject to search. An example used was that the U.S. cancer ratio is roughly 4 to 1. In Hopi Indian tribes, the ratio was 1,000 to 1 until supermarkets were built around their areas and their diets changed from almost exclusively alkalizers to a more acidic base. An interesting little tidbit as well is that it takes 22 or 23, I forget, glasses of water to offset the acidity from one soda to neutrality.

 

[iansmith]

champ2823

do you have any scientific references for the stuff just mention

 

[Evo]

I drink green tea as well. Actually to think about it I only drink teas, iced teas, water, and alcohol. No sodas for me. When I feel like I'm getting sick I take Echinacea and I already have a high Vitamin C intake daily and have found that I haven't been sick in a couple years.
Another thing with Green Tea is that it is an alkalizer and Nobel Peace Prize winners have done research on the affects of PH balance in your body. When I had my aquariums set up, ph was a big issue as if it got too high or low, my fish would be on their way down the toilet. Likewise, our body has a normal ph level beween 7.0 and 7.3 or closely similar dependent on the source. Anyways, these scientists as well as many scientists and doctors today have done research on ph levels relevant to people who are sick with just about anything like influenza, cancer, etc. Their findings conclude that cancer patients, etc., almost always have an abnormally low acidic ph. By raising the ph level of those people to alkaline, it has resulted in the cancer going away. The results are pretty mind boggling but this practice isn't really done in the U.S. where chemotherapy is primarily used with little proven results...but it's very expensive. In Europe, the ph thing is growing rapidly in popularity. It's really an interesting subject to search. An example used was that the U.S. cancer ratio is roughly 4 to 1. In Hopi Indian tribes, the ratio was 1,000 to 1 until supermarkets were built around their areas and their diets changed from almost exclusively alkalizers to a more acidic base. An interesting little tidbit as well is that it takes 22 or 23, I forget, glasses of water to offset the acidity from one soda to neutrality.

It sounds like you've been watching coral calcium infomercials. Please post links to valid scientifc/medical sources to back up your claims.

 

[gerben]

As far as I am aware, cholesterol levels are irrelevant to cardiovascular health. Green tea inhibits oxidation, which is important for cardio health, of both HDL and LDL and in fact LDL may have positive health impacts (as long as it is not oxidized). Fish oils are toxic if they are oxidized, yet they are beneficial to health if they are not oxidized. Perhaps high LDL levels became associated with cardio disease because the LDL in the persons measured tended to be oxidized and therefore toxic.

Your brain is composed of LDL, by the way. Reduce LDL and you suffer diseases of demyelination including adult-onset mental-retardation. Completely remove LDL from your body and you die.

HDL, on the other hand (being more protein and less lipid), is harder to oxidize. Therefore it gets the label from journalistic (and not scientific) medicine of "good cholesterol," though it may in fact be quite harmful to raise it in comparison with the possibly much-more-important-for-health LDL.

LDL’s can build up in the walls of arteries and form so-called plaques that can block the arteries, a condition called artherosclerosis. If this happens in the arteries that supply parts of the brain or the heart with oxygen this can lead to a stroke or heart failure. This is the reason they are associated with “cardio disease”.

HDL’s do not build up in the walls and carry cholesterol that it picks up at various places to the liver, where it is broken down. It is also believed that HDL tends to remove cholesterol from plaques in arteries and will in that way counteract the clogging of arteries.

Even without looking at the way it works it is simply a statistical finding that people with a high ratio of total (LDL and HDL) cholesterol to HDL cholesterol have higher chances of heart disease than people with lower ratios.

The brain is not made from LDL. It consists for a large part of fats and needs fatty acids to make these. Fats in your food are broken down to fatty acids. The fats that are used in the central nervous system are built within the central nervous system form these fatty acids.

...Currently, there is no evidence for the net transfer of sterol from the blood into the brain or spinal cord. In adults, the rate of synthesis exceeds the need for new structural sterol, so that net movement of cholesterol out of the CNS must take place...
http://www.jlr.org/cgi/content/abstract/45/8/1375

 

[hitssquad]

Unoxidized LDL is not a health threat

LDL’s can build up in the walls of arteries

Only oxidized LDLs do this. "Our findings demonstrate the presence of oxLDL in vivo, its strong association with coronary artery disease [...]"
ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=16028367

The brain is not made from LDL.

The brain is made from LDL.
ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=10867025

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Lipids and proteins from human low density lipoproteins (LDL) and high density lipoproteins (HDL) were taken up by distal axons and transported to cell bodies, whereas cell bodies/proximal axons internalized these components from only LDL, not HDL. Consistent with these observations, the impairment of axonal growth, induced by inhibition of cholesterol synthesis, was reversed when LDL or HDL were added to distal axons or when LDL, but not HDL, were added to cell bodies.
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[selfAdjoint]

The brain is made from LDL.
ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=10867025

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Lipids and proteins from human low density lipoproteins (LDL) and high density lipoproteins (HDL) were taken up by distal axons and transported to cell bodies, whereas cell bodies/proximal axons internalized these components from only LDL, not HDL. Consistent with these observations, the impairment of axonal growth, induced by inhibition of cholesterol synthesis, was reversed when LDL or HDL were added to distal axons or when LDL, but not HDL, were added to cell bodies.
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Which goes to show that the brain USES LDL but not that the the brain is MADE of LDL.

 

[gerben]

The brain is made from LDL.
ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=10867025

--
Lipids and proteins from human low density lipoproteins (LDL) and high density lipoproteins (HDL) were taken up by distal axons and transported to cell bodies, whereas cell bodies/proximal axons internalized these components from only LDL, not HDL. Consistent with these observations, the impairment of axonal growth, induced by inhibition of cholesterol synthesis, was reversed when LDL or HDL were added to distal axons or when LDL, but not HDL, were added to cell bodies.
--

This does not state that the brain is made from LDL. It reports that lipids and proteins from LDL and HDL where internalized. LDL is a complex that is used to transport cholesterol and lipids through the bloodstream not a “building block”.

(Also this is an unusual situation, they found that this can happen during axon regeneration; normally the needed cholesterol is synthesized within the brain. Here is the whole article: http://www.jbc.org/cgi/content/full/275/26/19883)

 

[DocToxyn]

I find when I feel a cold coming on if I drink 5-6 servings of green tea that I feel better the next day. Could that be attributed to the antioxidents in the tea? I don't know of any other teas that work the way green tea does. Does anyone know of a tea with similar effects to green tea?

~Kitty

You might try white tea, it is becoming more popular these days so you should be able to find it. All true teas (black, oolong, green, white, etc...) come from the same plant, Camellia sinensis. The differences in flavor, aroma, etc of the endproduct have to do with harvesting and processing practices. The white teas are generally processed the least and therefore are believed to contain more of the benefical polyphenolic compounds like the catechins EGCG, ECG, EGC... Green teas are processed a little more and thus are likely to have less of the agents, black and oolong with their associated fermentation processes have the least. There is a growing body of research into the health benefits of white teas and they are generally finding similar conclusoins as to what is reported with the green tea field.

 

[hitssquad]

Theaflavin. The other outperforming tea polyphenol.

The white teas are generally processed the least and therefore are believed to contain more of the benefical polyphenolic compounds like the catechins EGCG, ECG, EGC.

Black tea contains beneficial polyphenols, such as theaflavin, that are not found in other teas.
ncbi.nlm.nih.gov/entrez/query.fcgi?CMD=search&DB=pubmed&term=theaflavin

 

[champ2823]

No I haven't been watching Coral Calcium infomercials.
Give me a couple of days to go back and get the research and I'll post up the links.

 

[hitssquad]

Give me a couple of days to go back and get the research and I'll post up the links.

http://www.google.com/search?q=hopi+ph+cancer

24,500 hits for <hopi ph cancer>.

Aubrey K. Brewer's 1984 paper is online with full citations:

http://www.mwt.net/~drbrewer/highpH.htm

More about him here:

http://www.mwt.net/~drbrewer/brew_art.htm

 

[Evo]

http://www.google.com/search?q=hopi+ph+cancer

24,500 hits for <hopi ph cancer>.

Aubrey K. Brewer's 1984 paper is online with full citations:

http://www.mwt.net/~drbrewer/highpH.htm

More about him here:

http://www.mwt.net/~drbrewer/brew_art.htm

Everything I find on this guy links him to alternative medicine sites.

 

[TRCSF]

I think this is a pretty good starting point:

http://lpi.oregonstate.edu/infocenter/phytochemicals/tea/index.html

 

[Evo]

Great site on tea, thanks!