Everyone has heard that green tea is good for them. That is one of those universal truths that people talk about all the time.
But do you actually know why green tea is so great?
Let me spell it out for you: E-G-C-G. Epigallocatechin 3-gallate.
Yeah, I didn’t know what that was supposed to mean either….so I looked it up.
EGCG is an antioxidant compound found in large concentrations in green tea that is responsible for many of it’s health benefits.
There is far less EGCG in black or oolong tea, so if you want to get most of these extremely awesome benefits, you’ll need to stick with the green stuff.
There’s more to it than just the EGCG though.
There are many compounds found in green tea that contribute to its health benefits, and the way these compounds work together is not completely understood. But whatever the cause, here are a whole bunch of reasons to drink green tea:
1. Green Tea Will Keep You Alive.
According to this prospective study, consumption of green tea decreases all-cause mortality.
Consuming green tea makes you less likely to die at any given age! How awesome is that?
Men who drank five or more cups per day had a 12% lower risk of dying from any cause than those drinking less than one cup per day, and for women, the risk was a whopping 23% lower!
Some of you skeptics out there might be wondering if that benefit was confounded by other factors. After all, many people who drink green tea do so for health reasons, and these people are more likely to practice other healthy behaviors.
That’s a fantastic point….except that this study took place in Japan, where green tea is the most commonly consumed beverage, so it’s unlikely that this would be the case.
2. Green Tea Helps You Stay Alert.
To anyone who actually drinks green tea, this is no surprise.
Green tea contains caffeine (if you want to quit caffeine, check out that link), which as we all know helps keep you awake and alert. Although it varies per cup, I’ve usually seen green tea containing between 20-40 mg of caffeine, compared to a typical cup of coffee having 80-120 mg.
But that is old news.
What’s really interesting is that tea consumption causes comparable levels of increased alertness as coffee but doesn’t disrupt sleep as much.
Better sleep means more alertness overall, so I think tea is the winner here.
3. Green Tea Helps You Stay Relaxed.
The way I like to describe the effect that consuming green tea has on me is “relaxed alertness”.
I am perked up by the caffeine, but I still feel calm and don’t get any of the nervousness or irritability that coffee will sometimes give me.
This difference is because green tea contains significant quantities of theanine, a compound that has considerable stress-reducing effects. In fact, it has been shown that theanine reduces physiological responses to stress, such as heart rate.
4. Green Tea Keeps You Hydrated.
Of course staying hydrated is a priority for someone who cares about their health.
It is a common myth that consuming beverages containing caffeine will cause you to become dehydrated.
I understand where this is coming from about as well as anyone who has had several cups of tea before a class far from bathrooms…the diuretic effects can be downright brutal!
The reality, though, is that small amounts of caffeine (3 mg/kg) are not particularly diuretic. Larger quantities act as a diuretic in the short term, but within a few hours the overall fluid loss evens out.
And in the long term (several days), even large doses of caffeine (6 mg/kg/day, or approximately 4 cups of coffee for a 150 lb person) doesn’t change fluid status.
So in addition to green tea having all the benefits discussed in this article, it works just as well as water to hydrate you. You have no excuse to not be drinking a million cups per day.
5. Green Tea Prevents You From Dying Of Cardiovascular Disease.
The same study that shows you have lower all-cause mortality if you drink green tea suggests that its prevention of death by cardiovascular disease is one of the primary reasons.
In fact, if you are a man, you have a 22% lower risk of dying from cardiovascular disease if you drink loads of tea, and women have an even greater benefit: a 31% lower risk of death from cardiovascular disease!
6. Green Tea Prevents You From Dying Of Stroke.
I’ve always imagined that having a stroke would be just a horrendous experience. It’s just one of those things that seems best to avoid at all costs.
So when something comes along that’s both delicious AND decreases my risk of dying from a stroke by 42%, I take note.
Gentleman, that is a huge difference.
And ladies, you seem to be getting lucky with this whole green tea thing; you have a 62% lower risk of dying from stroke if you consume five or more cups of green tea per day.
7. Green Tea Protects You From Coronary Artery Disease.
Those drinking five cups per day of green tea were 16% less likely to develop coronary artery disease than those drinking three cups per day.
For those of you who know your statistics, the p-value in this study was less than .001.
For those of you who don’t know your statistics, that means the findings were very significant, and almost certainly caused by the difference in tea consumption.
8. Green Tea Lowers The Risk Of Atherosclerosis.
This study on hamsters showed that low amounts of tea decreased the incidence of atherosclerosis by 26-46%, and larger amounts decreased it by 48-63%. The quantities converted to reasonable human equivalents, so these findings are very noteworthy.
This human study shows that atherosclerosis risk can be decreased by consuming green tea, at least in men. Interestingly, the relationship did not exist in women.
But hey, women still get that lower mortality, so I think you ladies still come out winners in the end.
9. Green Tea Is A Blood Thinner.
Blood clotting is a necessary function of the body, but consuming pro-inflammatory foods can cause too much of it.
Platelets can clump together and cause obstructions that interfere with normal functioning of organs. Blood clots that get stuck in an artery can cause heart attacks and death! Bad news.
Luckily, the mechanism through which green tea seems to thin the blood is one that prevents the effects of the pro-inflammatory foods but wouldn’t prevent normal, healthy blood clotting.
Note: If you are taking blood thinning medication, you should ask your doctor before consuming green tea. It might be a bad idea, in case they interact. Don’t say I didn’t warn you.
10. Green Tea Speeds Up Recovery From Heart Attacks.
This benefit doesn’t apply to everyone out there, but it could be almost magical for those who do benefit.
People who consumed at least two cups of tea per day in the year before a myocardial infarction had a 39% lower mortality rate after the event.
This study details some of the protective mechanisms that EGCG has on the heart muscle following ischemia (restriction of blood flow, and therefore nutrients and oxygen).
To be honest, I don’t fully understand the scientific terms included there, but it involves preventing inflammation and oxidative damage. The same researcher who conducted that study says that EGCG helps the heart tissue recover faster, in addition to having less damage.
11. Green Tea Helps Protect The Brain After Strokes.
Those same mechanisms that I don’t understand in the above study seem to also have a protective effect on brain cells in individuals who have had strokes.
In a study on gerbils, administration of EGCG immediately after inducing a stroke had a significant effect in reducing neuronal damage.
Another study showed that pre-treating rats with green tea extract both promoted quicker recovery and minimized oxidative damage after inducing stroke.
12. Green Tea Prevents Hypertension.
Green tea extract helped to prevent hypertension in a study using male rats.
Of course, human studies are far better than animal studies, so how about this one? Habitual consumption of green tea for a year or longer resulted in drastically reduced risk of hypertension.
The reduction in risk was 46% for moderate drinkers, and a whopping 65% in those who consumed more than 600 mL/day. Since one cup is approximately 235 mL, this corresponds to about two and a half cups per day to qualify as a heavy tea drinker.
That’s a huge risk reduction for such a small amount of tea!
13. Green Tea May Protect Against Cancer.
The relationship between green tea consumption and cancer has been studied quite thoroughly.
It turns out that EGCG looks very similar to a particular cancer drug and utilizes the same mechanism of action. It inhibits an enzyme dihydrofolate reductase (DHFR) which cancer cells need to grow. How about that?
Green tea has plenty of other cancer-protective effects as well, but I thought that was a really neat one.
There is at least some evidence in human studies to suggest that green tea is protective against colo-rectal cancer, prostate cancer, ovarian cancer, lung cancer, bladder cancer, esophageal cancer, pancreatic cancer, and probably more that I haven’t mentioned.
For most of these cancers, human research is still not conclusive. But green tea consumption appears to have some beneficial effects with regards to cancer.
In the interests of brevity, I will only specifically talk about prostate cancer in this section. After all, women are still “winning” in terms of the benefit they get from green tea, so I will try to even the score a little bit.
In men with high-grade intraepithelial neoplasia (yeah, I don’t know what it is either), it has been shown that about 30% would develop prostate cancer within one year.
But with the administration of green tea catechins, only one of thirty who were treated developed prostate cancer within a year. The control group had nine individuals developing prostate cancer, as would be expected.
Big difference, fellas.
14. Green Tea May Help Prevent Gallstones.
Green tea may help prevent the development of gallstones and cancer of the gallbladder.
Individuals who drank at least one cup of green tea per day for at least six months had a 27% lower risk of developing gallstones and a 44% lower incidence of gallbladder cancer.
That’s an awful lot of protection for a very small amount of tea.
15. Green Tea May Protect The Lungs Of Cigarette Smokers.
In mice that were given a carcinogenic agent found in tobacco, those that were not treated with green tea or EGCG developed nearly double the number of lung tumors as the green tea treated mice.
But what about human studies?
Four cups of green tea per day reduced DNA damage in smokers. And smokers who drank more than one cup of green tea per day were considerably less likely to develop lung cancer than those who did not drink it…at least in that study.
On the other hand, this study found that green tea consumption reduced the risk of lung cancer in non-smokers, but not in those who smoke.
I guess the evidence is inconclusive for now, but promising enough to warrant further research.
16. Green Tea Improves Insulin Sensitivity.
Insulin sensitivity is an important factor in maintaining body weight and preventing type 2 diabetes.
Insulin is a hormone that takes sugar from the blood and shuttles it into other cells. You want higher insulin sensitivity so that your body doesn’t need to produce as much insulin to get the job done. Over time, if you become insulin resistant (low insulin sensitivity) you can develop diabetes.
In diabetic mice, EGCG significantly increased insulin sensitivity. Consumption of green tea increased insulin sensitivity in healthy rats.
Another study confirmed that the body’s ability to utilize blood sugar was improved after healthy humans consumed green tea.
These studies are very promising considering how common obesity and type 2 diabetes are in America.
17. Green Tea Protects Your Kidneys.
Your kidneys are pretty darn important.
So when scientists tell you that EGCG protects the kidneys from oxidative damage and prevents the formation of kidney stones, you should take notice. I’ve never had kidney stones, and I want to keep it that way.
In case you have diabetes, green tea provides additional benefits. It has been shown in diabetic rats that green tea consumption decreases the accumulation of glycogen in kidney tubules, thus preventing damage to the kidneys.
18. Green Tea Helps Build Stronger Bones.
This is a benefit that I would not have expected to come from drinking green tea, but hey, I’ll take it!
People who have habitually consumed tea tend to have significantly higher bone mineral density, especially if they have been habitual tea drinkers for more than ten years. Better get started now…
Another study found that EGCG stimulated osteogenesis, which would help explain how it increases bone mineral density.
In Britain, tea consumption was found to correlate with significantly higher bone mineral density in older women, and might help prevent osteoporosis. It’s also been shown that green tea may help lower the risk of fractures in elderly men and women.
19. Green Tea Is Good For Your Teeth.
Despite tea’s unfortunate tendency to stain or discolor your teeth, it’s actually quite healthy for your mouth!
A recent epidemiological study concluded that periodontal disease had a moderate inverse association with green tea intake.
Why might this be?
The bacteria P. gingivalis is responsible for most gum disease. This bacteria produces byproducts that are toxic to your mouth. Polyphenols from green tea completely inhibited the production of acids by this bacteria that would harm your teeth and gums.
Bonus: Since bad breath is usually caused by those same bacteria, drinking green tea will help keep your breath fresh!
20. Green Tea Protects The Liver From Alcohol.
Your liver is a very important organ because it is responsible for detoxifying a wide range of substances, most notably alcohol. A recent literature review concluded that green tea consumption may reduce the risk of liver diseases.
In rats chronically intoxicated with alcohol, green tea was shown to prevent most of the changes that would occur in the liver due to it’s high antioxidant activity. Another rat study found that green tea was able to blunt the effects of alcohol and prevent early alcohol induced liver disease.
This seems like an appropriate time to share one of my favorite drinks.
Make yourself a cup of tea, mix in some honey, and pour in a shot of brandy (approximately 4 parts tea to 1 part brandy). You wouldn’t think alcohol in a hot drink is good, but this is delicious. Give it a try, and leave a comment letting me know what you thought!
Serving suggestion: have one of these when you are coming down with a cold during the winter.
21. Green Tea Helps You Burn Fat.
Oh lordy, this is a big one. It’s not as though drinking green tea will make you thin by itself (if only), but anything that helps should be considered a positive, right?
A study on Japanese men and women with visceral fat (visceral fat is responsible for the “apple” shaped body) type obesity found that green tea extract reduced body fat. Another study confirmed these reductions in body fat, but this study was done primarily on healthy, non obese individuals.
So, how does this work?
I could easily write a whole article on the topic, but we’ll start with just the basics here. Gastric and pancreatic lipase are enzymes that help digest triglycerides. Fatty acid synthetase is an enzyme that converts fatty acids into the form necessary for them to be stored in fat cells.
Green tea inhibits these enzymes, which clearly would result in lower body fat.
22. Green Tea Helps You Exercise For Longer.
Remember what I just said about green tea helping the body to burn more fat?
Well it seems like the same mechanism that helps burn fat can lead to improvements in exercise endurance!
Since the body uses more fat, it then uses fewer carbohydrates in the form of stored glycogen. The stored glycogen lasts for longer, so you can use it for energy while exercising for an extended period of time!
On the other hand, a small study of human cyclists found that three weeks of supplementation with catechins from green tea found no measurable effect on time to exhaustion.
I would not take this as strong evidence against the possibility of increased exercise endurance because the amount of catechins used were the equivalent of less than two cups of tea, there was a small sample size, and treatment was only three weeks of supplementation.
Approximately four cups per day is the equivalent to the dosage used in the study on mice from the first paragraph. You’ll need to consume this regularly, for at least a few weeks before there would be any effect on exercise endurance.
23. Green Tea May Prevent Alzheimer’s Disease.
Personally, I love my brain.
My #1 fear from a health standpoint is getting Alzheimer’s disease.
While there are not yet any conclusive studies of tea’s effects on Alzheimer’s in humans, animal and cell culture studies leave us reason to be hopeful.
EGCG has been shown to bind to and remove iron from the brain, which helps prevent oxidative damage associated with Alzheimer’s. It also stimulates antioxidant systems which further prevent damage.
24. Green Tea May Prevent Parkinson’s Disease.
Many of the same processes which help fight against Alzheimer’s also apply to Parkinson’s disease. EGCG and other antioxidants are neuroprotective through a number of biological mechanisms.
In addition, EGCG prevents damage to dopamine neurons when exposed to a neurotoxic chemical. This protective effect could be a model of how it might prevent Parkinson’s.
25. Green Tea Prevents Cognitive Decline In General.
While evidence of preventing neurodegenerative disease is still preliminary, you can be confident that consuming green tea will keep you sharp as you get older.
This study showed that consumption of even small quantities of green tea prevents cognitive decline in the elderly.
Those drinking two or more cups per day had a 54% lower risk of age related decline in memory, ability to follow commands, and other parameters. Those drinking just one cup per day had a 38% lower risk of a decline in brain function.
Sounds like a no-brainer to me. Ugh I hate myself for making that pun.
26. Green Tea May Help You Stay Healthy During Flu Season.
EGCG has antiviral properties, and has been shown to inhibit the proliferation of influenza virus in cell culture.
Sure, as of right now, we can’t say for certain whether or not consumption of green tea will lower the severity or duration of flu symptoms or whether it can help prevent contracting the virus altogether, but this evidence is promising.
EGCG causes changes in the viral membrane itself…cool!
27. Green Tea Can Protect You From Deadly Infections.
Did you know that the bacteria that causes strep throat can actually be deadly?
My mom told me just last weekend of someone she knew who was infected with the streptococcus pyogenes bacteria but did not show any symptoms (and therefore didn’t get treated), and died of sudden kidney failure in his 30s.
I know, it’s such a downer to bring up. Sorry about that. I mention it because I had assumed it was an uncommon thing, but apparently it happens more than I first thought.
Anyways, EGCG inhibits the ability of this bacteria from clinging to host cells. It can also induce bacterial cell death. So basically, it makes it considerably harder for S. pyogenes to cause an infection in your body.
It may only prevent a sore throat, or it also could save your life.
28. Green Tea Allows You To Experience A Very Unique Flavor.
We’ve all heard of the four basic tastes: sweet, salty, bitter, and sour.
But not everyone is familiar with the fifth taste, or umami. In fact, WordPress doesn’t even recognize it as a word. It means “delicious” in Japanese. The source of umami flavor is the amino acid l-glutamate.
Umami is a hard to describe taste, but I feel like it involves a certain texture or feeling in the mouth more than the other tastes do.
There are a number of other foods that are rich in umami, but green tea is unique in that it has both theanine and glutamate. Theanine also contributes umami (and some sweetness) but is only found in substantial amounts in tea, and thus provides a very pleasant one-two punch of umami flavor. Delicious!
29. Green Tea Has A Wide Range Of Possible Short-Term Cognitive Benefits.
From a very un-scientific standpoint, I feel like I am “smarter” or more capable of performing intellectual tasks after consuming green tea.
That could very well be a placebo, but there is real evidence of some possible benefits.
Caffeine and theanine are the two compounds in green tea that are most widely studied with regards to cognitive function.
Even low doses of caffeine have been shown to improve measures such as reaction time and rapid visual information processing.
Combining caffeine and theanine strengthened the cognitive benefit. Together they improve some aspects of memory and attention more so than caffeine alone.
In a 2008 study (Owen, et al), most notable was the improvement in attention switching tasks; the combination resulted in better speed and accuracy.
I should point out that this study used a ratio of theanine to caffeine that is different from what is found in green tea, and thus further research is needed to describe the precise nature of the cognitive benefits.
30. Green Tea Is Good For Your Skin.
Topical treatment with EGCG before exposure to UV-B radiation significantly improved several markers of skin damage compared to a control group.
That’s all well and good, but I’m not gonna pour hot tea all over my skin before a day at the beach. So what are the effects of oral consumption of green tea on the skin?
More research needs to be done on humans to say for sure, but animal studies are promising.
In a study on mice, it was found that both topical treatment and oral ingestion of green tea extract significantly reduced the incidence of tumors after exposure to UV-B radiation, and the effect was stronger in the oral ingestion group.
Another study on mice found that oral consumption of both green tea and caffeine up-regulated a tumor suppressor gene in response to UV exposure. This could be one mechanism by which green tea protects against skin cancer.
I’ve spent a grand total of about 14 hours researching and writing this blog post, and I’ve had a cup of delicious green tea at my side for the entire time.
I’m pretty sure I’m now invincible.
This blog is about how to live a happier and healthier life. You would be doing a disservice to yourself if you didn’t at least try to make green tea a part of your life, considering both the beneficial subjective effects and the multitude of health benefits.
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