In this article, we first explain why green tea constipation can happen to certain drinkers who are very sensitive to the tannins and caffeine content.
In a second section we present how, if consumed in normal quantities, green tea can actually be used as constipation remedy. Green tea can allow more bile to stay within your stools, bile being our natural laxative. This does not contradict the first point; it is all a question of quantity ingested.
Thirdly, we spend some time on the benefits of green tea on the overall gastrointestinal tract, from mouth to colon. We will see that the benefits for constipated people far outweigh the risks, assuming we stay within reasonable consumption ranges.
Along the way, we provide important preparation tips to make sure you get the good components in your cup, leaving those that can cause constipation in the sink.
So brew yourself a cup, and read on!
We will explain why tea is such a wonderfully healthy drink in the second section. For now, we are focusing on why green tea can provoke the "green tea constipation" phenomenon.
The two main constituents responsible for constipation are :
Green tea contains a significant quantity of tannins, in the form of catechins. Depending on the type of crop and picking season, a green tea leaf can contain from 10% to 15% of catechins.
The tannins are responsible for the astringent taste, the mouth puckering effect of green tea.
As their name indicates, tannins have an ability to “tan” our tissues, our skin and mucosa. When you apply this tanning process to our gastrointestinal mucosa, our secretions are disturbed.
Imagine our gut mucosa: moist, loose, flexible, letting secretions from different glands embedded in the tissues do their work and release enzymes and other liquids into the interior of the bowel.
Tannins are going to shrink those tissues, close those pores, as if you were tanning a hide, the texture becoming very close-knit and waterproof.
At its core, constipation is a lack of fluid in feces (for a list of the different causes of constipation, see this article). Disrupt the fluid balance in your gut, and you run the risk of green tea constipation.
We have been told that green tea contains much less caffeine than other caffeinated drinks. This is true. But it still has a certain, non-negligible amount.
The following table provides the caffeine content of different drinks (obtained from the Wikipedia website, caffeinepage):
|Beverage||Serving size||Caffeine per serving (mg)|
|Jolt Cola||695 mL (23.5 U.S. fl oz)||280|
|Drip coffee||207 mL (7 U.S. fl oz)||115–175|
|Coffee, espresso||44–60 mL (1.5-2 U.S. fl oz)||100|
|Red Bull||250 mL (8.2 U.S. fl oz)||80|
|Mountain Dew||355 mL (12 U.S. fl oz)||54|
|Black tea||177 mL (6 U.S. fl oz)||50|
|Coca-Cola Classic||355 mL (12 U.S. fl oz)||34|
|Green tea||177 mL (6 U.S. fl oz)||30|
As you can see, green tea is at the bottom of the list, containing one third the amount of a cup of expresso.
But drink 3 cups of green tea, and you’re there. Drink 6 cups and you have the amount of 2 espressos. If you have a tendency to be constipated, and if stress is a trigger, this can be problematic.
As we have seen in our series of introductory articles, stress is our innate response to imminent danger. It prepares us for fight or flight. It shunts blood circulation and reroutes it towards organs vital for survival – our heart, lungs, muscles, etc.
Is the gastrointestinal tract vital for fight or flight? Not at all. On the contrary, it’s a detour.
Stress cuts a portion of the blood supply to your gut. Less blood means less function. Less function means fewer secretions, and less forward movement, with stools spending longer in the colon getting dehydrated, and obtaining less fluid from the gallbladder. Not good, leading to the green tea constipation phenomenon.
Green tea constipation does not occur after a couple of daily cups. The problems of tannins and caffeine start when you ingest a much larger dose.
It depends how sensitive you are to tannins and stress. You have to judge for yourself. By all means drink green tea, but stay at the level where you get all the benefits without the drawbacks. Experiment.
And the exciting part is that there is a way to prepare green tea to get rid of the caffeine and limit the risks of green tea constipation.
To avoid green tea constipation due to too much caffeine, prepare your tea the following by:
This method ensures that you get most of the beneficial antioxidant compounds, without ingesting too much caffeine. Some of the tannins will also be evacuated. This is worth trying for cases of green tea constipation.
Here is the up side. In the previous section we discussed green tea constipation and the reasons behind it. However, if consumed daily in a reasonable quantity, green tea can actually provide constipation relief.
What is a reasonable quantity for you? You will have to experiment. But I would say that 3 to 4 cups a day should not create green tea constipation issues. Imagine a scale. On one side is constipation relief, on the other side is green tea constipation. What tips the scale one way or another is the number of cups you drink.
Green tea helps your transit by keeping more bile in your gastrointestinal tract. Said bile will eventually be excreted in your stools, providing more moisture. You will remember from the introductory sections that bile is our natural laxative.
Multiple scientific studies have confirmed this fact.
One study(1) found that green tea lowers serum (blood) and liver cholesterol. The researchers discovered that the lower amount of blood cholesterol was due to a significant increase in fecal bile and fecal cholesterol (more bile and cholesterol in your stools means more lubrication).
Another study(2) found that the green tea catechins have an inhibitory effect on intestinal bile acid absorption. The first study shows that green tea makes you excrete more bile. This second study explains that green tea decreases the activity of our intestinal bile transporters responsible for re-absorption of bile acids into our system which means more bile available to moisten your stools.
The evidence is unequivocal. As bile is our natural laxative, green tea contributes to our constipation relief effort.
A STANDALONE CONSTIPATION REMEDY?
The question is, can green tea be used as standalone constipation remedy? Can it, by itself, eliminate constipation?
I don’t believe so. I have worked with enough constipated patients in my naturopathic practice to know that the chronically constipated need a list of constipation remedies. They need a portfolio of natural cures for constipation, to be able to use multiple remedies at the same time, or to alternate from one to the other when one stops working.
Green tea makes tremendous sense as part of a broad-based constipation remedies toolkit. But it doesn’t stand much chance on its own. Make it part of your daily routine. Don’t hesitate; in reasonable quantities green tea packs significant health benefits.
In any case it will protect your gastrointestinal tract.
Green tea is a pretty amazing drink, backed up by decades of scientific studies.
It can contribute to stability and health of your bowel as long as the daily dose remains below your “constipation trigger” dose.
The following digestive organs benefit from green tea consumption:
As I said, this is a powerful drink protecting you almost “from head to toe”. The benefits far outweigh the risks of getting green tea constipation.
We tend to forget that digestion starts in the mouth. A healthy mouth environment, with appropriate secretions of enzymes, promotes good digestion.
As in the gut, we have active flora in the mouth, constituted of multiple strains of friendly bacteria. And, as with the gut, some strains are not so friendly and are responsible for cavities. Two of these unfriendly strains are mutans streptococci and lactobacilli.
Studies(3) show that a rinse of green tea extract reduces the levels of mutans streptococci and lactobacilli in saliva. Less pathogenic bacteria, fewer cavities, and better mouth flora can only promote better digestion in the long run.
Stomach ulcers are a major problem today, particularly for those taking a lot of non-steroidal anti-inflammatory drugs (NSAIDs).
Studies(4) show that green tea catechins can partially reverse the oxidative stress created by NSAIDs. These studies remind us that green tea catechins are non-toxic, inexpensive and constitute an "excellent candidate for further evaluation as a potent anti-ulcer drug".
The liver is the main processing plant of the digestive system.
If the mouth and gut are the dis-assembly chain, the liver is the great organizer and re-assembler, making sure the essential constituents we ingest are combined before being sent in general circulation to feed our cells.
The liver also secretes bile, our natural laxative. A healthy liver creates a healthy flow of bile which participates in keeping us constipation-free.
Studies(5) show that green tea extract significantly attenuates the oxidative stress and inflammation created by alcohol intoxication. It also helps reduce lipid accumulation in the liver, which can lead to steatosis, or "fatty liver".
The pancreas releases multiple digestion enzymes. A healthy pancreas is essential for healthy digestion.
Studies(6) show that green tea catechins reduce the damage created by a high-fat diet and protect the pancreas.
No need to belabor the fact that the health of the intestine is critical to having good bowel transit.
The fact is that more and more people today have inflammatory bowel conditions, whether due to diet, food sensitivities or other lifestyle factors.
We have seen that serious inflammation caused by colitis can create scar tissues in the intestine. Scar tissues reduce the flexibility of the intestine mucosa, can reduce the diameter of the “tube” and possibly lead to colon blockage.
Studies(7) show that green tea catechins inhibit inflammation created by colitis. In experiments, green tea catechins could significantly reduce the symptoms of colitis, namely bloody diarrhea, edema, and loss of body weight.
Daily consumption of green tea may therefore be beneficial in keeping bowel inflammation down and avoiding colon blockage in the long run.
Inflammation can occur in the colon, too, and eventually lead to feared colorectal cancer.
Studies show that green tea consumption of more than 10 cups daily reduced colorectal cancer risk in the Japanese population.
A study(8) shows that consumption of green tea extract can reduce the reoccurrence of colorectal cancer. The study took a sample of 136 patients who had removal of colorectal adenomas. The patients were then divided into two groups, a green tea group and a placebo group. The green tea group was given 1.5 gram of green tea extract each day for one year. Twelve months later, follow-up colonoscopy showed that the incidence of adenomas for the placebo group was 31%, and was only 15% in the green tea group! Relapsed adenomas were also smaller in the green tea group.
Another study(9) looked at Inflammatory Bowel Disease (IBD) and showed that green tea extract significantly reduced diarrhea and loss of body weight. This is associated with a "remarkable amelioration of the disruption of the colonic architecture".
I have been a regular green tea drinker for the last 15 years, and I have tried many different brands. I visited Japan multiple times, and had the chance to shop at large and prestigious tea shops, as well as small, family own stores. Things can get quite fancy, with the best green teas being drunk just like an old expensive wine.
But to me, this needs to be simple and down to earth. I have come to like and recommend green teas that are both affordable and of high-quality. Green tea has so many benefits that it should not be a product reserved for the elite classes. It needs to be democratized.
What about Fukushima?
Fukushima has made me wonder whether I should continue to drink green tea or not. The newspapers have been quick to scare people in 2011 based on a report published by the Japanese authorities.
On the other hand, after Fukushima, the FDA put a special emphasis on radiation testing for shipments coming from Japan. I quote from a bulleting published by the FDA :
"FDA’s screening at U.S. borders will remain vigilant and will be augmented with radiation screening of shipments. On March 22, 2011, in order to complement the measures taken by the Government of Japan and to strengthen the global food safety net regarding certain products [...]"
Green tea belongs to the FDA "category one", for which they say:
"Category 1 consists of products that the Government of Japan has restricted for sale or export. Authorities will prevent these products from entering the U.S. These products cannot gain entry by providing sample results. As of July 11, 2011, these include: Tea leaves from Ibaraki, Tochigi, Gunma, Kanagawa, and Chiba prefectures, and dace, ayu, and cherry salmon (yamame) from Fukushima."
In the end, this is a personal choice. Personally, I have decided to switch to quality Chinese green tea until the dust settles on that matter:
We have seen that people sensitive to tannins and caffeine can experience green tea constipation if they consume too much.
We also saw that a moderate consumption of a few cups a day can actually contribute to moister stools and reduced constipation.
But green tea cannot be considered a standalone constipation cure. It needs to be part of an anti-constipation lifestyle that includes diet, supplements, and medicinal plants.
Green tea provides amazing health benefits for the overall gastrointestinal tract, not to mention its protective effects for the cardiovascular and other organ systems.
Studies after studies show the superb health benefits of green tea. So, do yourself a favor. Buy good quality green tea leaves, and include a few cups in your anti-constipation lifestyle.
Kanpaï - to your health!
(1) Yang TT, Koo MW. "Chinese green tea lowers cholesterol level through an increase in fecal lipid excretion". Life Sci. 2000;66(5):411-23.
(2) Annaba F, Kumar P, Dudeja AK, Saksena S, Gill RK, Alrefai WA. "Green tea catechin EGCG inhibits ileal apical sodium bile acid transporter ASBT". Am J Physiol Gastrointest Liver Physiol. 2010 Mar;298(3):G467-73.
(3) Ferrazzano GF, Roberto L, Amato I, Cantile T, Sangianantoni G, Ingenito A. "Antimicrobial properties of green tea extract against cariogenic microflora: an in vivo study". J Med Food. 2011 Sep;14(9):907-11.
(4) Adhikary B, Yadav SK, Bandyopadhyay SK, Chattopadhyay S. "Epigallocatechin gallate accelerates healing of indomethacin-induced stomach ulcers in mice". Pharmacol Rep. 2011;63(2):527-36.
(5) Chen KH, Li PC, Lin WH, Chien CT, Low BH. "Depression by a green tea extract of alcohol-induced oxidative stress and lipogenesis in rat liver". Biosci Biotechnol Biochem. 2011;75(9):1668-76.
(6) Chen KH, Li PC, Lin WH, Chien CT, Low BH. "Depression by a green tea extract of alcohol-induced oxidative stress and lipogenesis in rat liver". Biosci Biotechnol Biochem. 2011;75(9):1668-76. Epub 2011 Sep 7.
(7) Abboud PA, Hake PW, Burroughs TJ, Odoms K, O'Connor M, Mangeshkar P, Wong HR, Zingarelli B. "Therapeutic effect of epigallocatechin-3-gallate in a mouse model of colitis". Eur J Pharmacol. 2008 Jan 28;579(1-3):411-7. Epub 2007 Oct 30.
(8) Shimizu M, Fukutomi Y, Ninomiya M, Nagura K, Kato T, Araki H, Suganuma M, Fujiki H, Moriwaki H. "Green tea extracts for the prevention of metachronous colorectal adenomas: a pilot study". Cancer Epidemiol Biomarkers Prev. 2008 Nov;17(11):3020-5.
(9) Mazzon E, Muià C, Paola RD, Genovese T, Menegazzi M, De Sarro A, Suzuki H, Cuzzocrea S. "Green tea polyphenol extract attenuates colon injury induced by experimental colitis". Free Radic Res. 2005 Sep;39(9):1017-25.