Green Tea for Pneumonia

Drinking green tea may be protective against pneumonia, a new study published in The American Journal of Clinical Nutrition suggests.

The study followed 40,572 National Health Insurance beneficiaries in Japan (19,079 men and 21,493 women) who were 40-79 years old and did not have histories of cancer, heart attack or stroke. Study participants were examined to determine the potential relationship between green tea consumption and death from pneumonia.

After 12 years of follow up, 406 out of the 34,539 participants included (6,033 lost to follow-up) died from pneumonia. However, drinking green tea daily was associated with significantly lower risks of death from pneumonia among women.

After adjusting for age, smoking status, physical functionality and other risk factors, drinking just one cup of green daily was linked to a 41 percent reduced risk of dying from pneumonia among women. Benefits were greater when green tea consumption increased, as women who reported drinking five or more cups a day had a 47 percent lower risk of dying from pneumonia. These results were not observed in men.

Of the many reported benefits of green tea, these data support the possibility that green tea contains components that help fight against viruses and bacteria. For instance, catechins, a main constituent of green tea, have been suggested to have antiviral activity according to experimental and animal studies.

The findings of this cohort study are suggestive, but drinking green tea is not yet recommended to replace current preventative techniques such as hand washing and yearly flu vaccination.

Other non-pharmacological therapies have also been tested for the prevention of pneumonia and pneumonia-related complications. Chiropractic and chlorophyll are just some of the other integrative therapies with potential immune-regulating effects and suggested protective benefits for pneumonia, but the evidence is not fully supportive.

For more information about pneumonia, please visit Natural Standard’s Medical Conditions database.

Comments

[CU]

It seems like green tea is being used for a variety of different ailments. I find it interesting that when consumption increased to five or more cups a day, women had a 47 percent lower risk of dying from pneumonia compared to men. What would be the explanation for this? Is there something physiological going on in women who consume green tea as compared to men?

[Natalie]

Hand washing and vaccinations will always be key components of infection prevention (pneumonia included). However, it is interesting to read how things look promising for green tea as an adjunct therapy. People are always looking for little ways to boost their immune system, and one cup of green tea a day seems like a realistic practice that people could fit into their lives. Sometimes studies only find significant results when the subjects consume unattainably large quantities of the substance in question. Even though the benefit increased with the amount ingested, it is encouraging to see that green tea may be beneficial in reasonable amounts as well.

[George]

This study makes it seem like the more green tea the better, but when does it become too much? I checked out Natural Standard’s green tea professional monograph and saw that each cup of green tea contains up to 50mg of caffeine. People with hypertension should avoid caffeine due to its stimulant properties.

Additionally women who are pregnant or nursing should avoid caffeine as well. Short- and long-term side effects can occur once daily caffeine consumption reaches 500mg. Other than that, green tea appears to be safe and non-toxic. As with any therapy, the benefit must outweigh the risk (in this case, pneumonia prevention vs. green tea’s potential adverse effects).

[Mike]

Green tea has been proposed to have many benefits in many systems in the human body, including reducing arthritic pain, asthma symptoms and anxiousness. It is interesting to read that components of green tea might be active against viruses and other pathogens. I would like to see if these data can be replicated in studies outside of Japan and in different populations because it is peculiar that green tea would only exert antiviral or bactericidal effects only in women, and this would definitely benefit from additional research. I am also curious as to why patients with histories of cancer and CV events were excluded. Death due to pneumonia could have also been present in this population, and I don't see any significant reason as to why this group was excluded.

[Sarah]

How come these results were not observed in men? What would be possible explanation(s)? Does the bacteria that causes pneumonia affect women differently than men? If so, please explain.

[Will]

What a delicious form of preventative medicine. I am definitely willing to bring my green tea habit up to daily if it can help keep pneumonia at bay. As an added bonus, I have found that I snack less in the afternoons when I have green tea with lunch.

[BW]

How many cups of green tea can you drink before seeing adverse effects? I know on Natural Standard’s monograph for green tea, says that for general purposes, 10 cups a day should not be exceeded. However, when treating cancer, some studies have shown that greater than 10 cups per day extended survival. So I’m curious as to what would be the maximum amount of green tea that can be consumed for pneumonia purposes.

[Liz]

What about the caffeine in tea though? I thought too much caffeine was bad for you. Does black tea and other herbal teas offer the same potential benefits?

[Robin]

It is very interesting that green tea consumption can decrease the risk of death from pneumonia in women. However, it makes me curious why these effects are not seen in men. If the proposed mechanism is the antiviral and antibacterial effects from the catechins in green tea, why don’t men get the same benefits from drinking green tea?

[Ben]

Actually, black tea has more caffeine in it than green tea, so if you are worried about caffeine content, green tea is a better choice for you. (Black tea = 45mg caffeine, green tea = 20mg caffeine)

[Willy]

This looks to be another easy way for people to stay healthy. Interestingly though, there was only a 6 percent lower risk when drinking 5 or more cups of green tea a day as compared to one. This is a very minimal decrease for the larger amount of green tea consumed. On the positive side, you don't have to drink large amounts to see the benefits.

Like others have commented, it's very strange that drinking green tea only lowered the chance of death from pneumonia in women and not men. Perhaps there were some confounding variables or limitations to the study. More studies should be done, hopefully involving people of different ethnic backgrounds.

[MN]

Green tea seems to always be associated with beneficial effects in many different health problems, including the common cold. So I’m not surprised that it may actually help protect against pneumonia in women as well.

However it’s interesting that this finding was not found in men because if it’s the catechins in the green tea that’s suggested to have antiviral therapy, then does it lack this activity in men? Also, is it possible that those who drank green tea were also more inclined to take better care of themselves and follow other measures that could further protect them from pneumonia? There seems that there could be a lot of contributing factors that may have affected the results. Regardless, I think it’s worth a try to have a cup of green tea a day, considering all the potential health benefits it may offer.

[thé]

Not to tempt fate, but I just don't get ill. I thought it was being vegetarian, but maybe it is the 1-2 big pots of green tea I get during the day?

While others around me get down and have colds and headaches and various ailments, I don't.

[Kity]

The study also mentioned that chiropractic may have “potential immune-regulating effects.” How would chiropractic protect against pneumonia? How does it have antiviral or antibacterial effect?

[Etta]

I think the answer to "how much is too much?" deals with the caffeine involved. I have heard that the adverse effects of green tea are directly related to caffeine levels. There are decaffeinated green teas available, but I don't know if they would have the same medicinal effects for pneumonia.

[Reg]

Interesting study on the connection between green tea consumption and pneumonia. The studied sample was large, so the results that drinking green tea protects one from pneumonia is promising. It is strange, however, that these results seems to be valid for women only, at least based on what has been reported. What happened to men? Is the green tea less effective for them?

[EH]

I have also wondered about the toxicity levels of green tea. What has interested me more, however, is that the hazard ratio was brought down tremendously from 1.00 for or =5 cups/d, respectively. So just by making a small change to add in one cup of green tea is enough to vastly cut down the risk.

[Sam]

I would be interested to see more specific baseline characteristics. Did the study participants receive flu vaccines or take vitamin C supplements? If so, it would be difficult to attribute pneumonia prevention to green tea unless all study participants received flu vaccine and supplements,

[JH]

Does the study say anything about the percentage of people actually consuming green tea? It mentions the thousands of participants, but that doesn’t necessarily mean all of these people actually drank the tea and on a consistent basis. Could a reason that benefits were higher amongst women be because they drank more tea than the men? Or another reason could be that they were more likely to report it. I know one issue with studies that require reporting is that men are less likely to report things. That is why issues like depression always appear skewed in the female direction.

[Luo]

JH brought up a good point about the possibility that women ha greater benefits than men because they were more likely to report changes with their health status. The study also reinforced what CDC recommends about the importance of hand washing. The CDC recommends washing the hands for 20 seconds with a regular soap or using a hand sanitizer that contains at least 60% alcohol.

[karina gordin]

I am quite fascinated by the role of green tea catechins in pneumonia prevention and applaud this study in further investigating the multitudinous role of polyphenols and alternatives to the acute lung disease.

However, the backbone of this article is undermined by the mainstream, and if I may add, rather misguided perception that a yearly flu vaccination is still the recommended mode of pneumonia prevention. "...the findings of this cohort study are suggestive, but drinking green tea is not yet recommended to replace current preventative techniques such as hand washing and yearly flu vaccination," particularly at a time when our reckless and unsuited President Obama declares the swine flu outbreak a national emergency. The article's obligatory caveat is unfortunately confirmed, but just a brief investigation into that statement opens the flood doors of havoc and sickness, paving a circuitous path ultimately to pneumonia.

I hope to live to see the day when "yet" is obsolete.

[T.b.]

For those concerned about the caffeine content in green tea, compare that to red bull and you will see twice the difference. And if it is still really a bother, adding lemon to the tea lowers the caffeine activity in the system.

[CD]

Green tea is so simple to add to your day. Take it in with your morning break at work and add some lemon to it. Studies have shown that by adding the lemon, you will increase the amount of antioxidants that you can take in. Without the lemon, a lot of the antioxidants get flushed out naturally of our systems, but by adding the lemon, you can naturally increase your body's ability to absorb so much more of the antioxidants available in this tea. So, next time you're drinking, have your fresh lemon slice nearby!

[Nina]

Green tea seems to make a great adjunct during the cold/flu season. Other studies (JM Song, 2005) also demonstrated green tea catechins and epigallocatechins activity against Influenza A and B viruses. The catechins have a mechanism by which they prevent viruses to adhere to cell walls. This study did not seem to have distinguished green tea as gender specific in terms of viral prevention.

[DB]

Wow, I never knew lemon had so many redeeming qualities. How does lemon lower the caffeine activity in your system? Is there some type of chemical reaction? That’s pretty fascinating. Does it lower it by a significant amount? Is it like a 50% reduction in caffeine? Also, the comment about lemons increasing your ability to absorb antioxidants -- is that also a chemical reaction in the body? Is there something special about a lemon that it can do all of these things? Can a lime do it? Is it confined to just lemons or do other citrus fruits have the same type of effects?

[Grace Caulfield]

It’s not surprising that green tea could be protective against pneumonia. It is well known for its powerful antioxidant effects, and it’s delicious! What more could you want?

[Sam]

The study focuses on the age group 40-79. I wonder if drinking green tea has been studied as a preventative measure against pneumonia in a broader age range, and if so, whether or not a similar trend was noticed. It will be interesting to see how research progresses on the efficacy of green tea.

[DF]

Besides drinking green tea, another way to help prevent pneumonia may be to avoid unnecessary use of acid-suppressing drugs. Two recent studies (JAMA, 5/27/09, and Chest, 8/09) have linked such drugs to an increased risk of developing pneumonia among hospital patients. Proton pump inhibitors (such as Nexium, Prilosec, and Protonix) may be more problematic than H2 blockers (such as Pepcid, Tagamet, and Zanctac). One theory is that suppressing stomach acid might allow more bacteria to flourish and travel to the lungs.

[Think]

It is very interesting article about green tea. It seems like green tea is so common in Japan; they drink green tea as daily fluid intake. I went to Japan and I saw more 10 brands of green tea water. That explains how big a sample size of this study could be possibly done.

Green tea became very popular in the U.S too -- it comes in the form of ice cream, cookies, even weight-loss pills.

I think this study will make green tea more popular, and I wonder if the study was supported by certain companies, or biased by any group of green tea fans. It is also very interesting that the study did not observe significant results in men. Usually men are 30% more likely than women to die from pneumonia, even if the severity of the illness is the same. It would have been very useful it the study showed results for both genders.

[Saman]

I wonder if these beneficial effects of green tea are observed when green tea is taken in combination with something else. For example, would green tea with a chai flavor still exert the same beneficial effects? It will be interesting to see how this is studied in the future.

[kim]

After reading this, I’m thinking I should really start drinking green tea. I have already heard so many other indications that green tea can be beneficial for, and now, green tea can also be protective against pneumonia.

However, I wonder how many other confounding factors were present in this study because I feel like a lot of outside factors could easily have an impact on the risk of dying from pneumonia.

It’s also interesting how this benefit was only seen in women and not in men. I wonder if the same effect would also be seen in other races as well since this study only followed Japanese patients.

[anon]

Lemon tends to counterbalance activities of the sympathetic nervous system. Adding a wedge of lemon or steeping half a lemon in a cup of green tea helps to lower caffeine activity.

[Tom]

A study in Japanese men showed that increased consumption of green tea is associated with decreased serum concentrations of total cholesterol and triglycerides and a lower atherogenic index.

http://www.ncbi.nlm.nih.gov/pubmed/7711535?itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum&ordinalpos=5

[Green Tea]

The benefits of green tea in a human body are so remarkable.It's very interesting that drinking green tea can decrease the risk of death from pneumonia in women. What about men? Is the green tea less effective for them?

[rsamd]

There are some difficulties in determining if green tea is the thing that helped prevent pneumonia in select patients, especially after 12 years of follow up. However, I have heard in passing that the catechins have some sort of protective activity against viruses. As mentioned previously, I wonder why the benefit was only seen in women. I think it’s an added benefit if it helps, but agree completely that more proven methods to protect against viruses (washing of hands and flu shots) should not be replaced.

[Extremely Motivated]

The research on green tea keeps on mounting. I am curious to know why women had a reduction in pneumonia, whereas this was not evident in men. This study is fairly large, which gives it better external credibility. Living in North America, our diets and lifestyles are significantly different from the Japanese population. I wonder if the results would be similar if the study was performed here in the United States.