Get the Most From Your Green Tea
Green tea, particularly the matcha variety, contains high amounts of the polyphenol epigallocatechin-3-gallate (EGCG), which has 25 to 100 times more antioxidant activity than vitamins C and E.
STORY AT-A-GLANCE
Green tea contains incredibly potent antioxidants, including the most prevalent and powerful catechin known as epigallocatechin-3-gallate (EGCG)
Studies show green tea consumption improves brain function, as well as staves off cognitive disorders such as Alzheimer’s, helps prevent dental cavities, fights inflammatory disease such as arthritis and even combats several cancers
How tea leaves are processed makes all the difference in the health benefits provided, as do the water temperature and steeping time
Editor's Note: This article is a reprint. It was originally published February 13, 2017.
If you've ever found it curious how devoted the English, Chinese and East Indians seem to be about keeping their tea times (not tee times), you might be interested to know that it often goes far beyond simple enjoyment and R & R. It's often just as much about the health benefits, which can relate to better health and longer life.
One of the most interesting paradoxes regarding tea, especially matcha green tea, is that it can soothe, calm and relax you while simultaneously intensifying your alertness.
One reason green tea is so good for you is because of its incredibly potent antioxidants. Like many fruits and berries, green tea contains high amounts of polyphenols, particularly a catechin known as epigallocatechin-3-gallate (EGCG). This most predominant antioxidant offers 25 to 100 times more antioxidant activity than even vitamins C and E.1
Rheumatoid arthritis (RA),2 Alzheimer's disease3 and cancer, particularly prostate cancer,4 for instance, are all diseases that researchers have noted are suppressed or killed (aka apoptosis-induced) by introducing EGCG nanoparticles.5 One study notes:
"Green tea's active ingredient, epigallocatechin 3-gallate (EGCG), has gained significant attention among scientists and has been one of the leading plant-derived molecules studied for its potential health benefits.
… [A]nother study found that catechins from green tea inhibited the degradation of human cartilage."6
There are just as many studies that show dramatic effects of green tea consumption on improved brain function, as well as staving off cognitive disorders such as Alzheimer's and dementia.
How to Get the Most Flavonoids From Your Green Tea
While there are many antioxidants in green tea, remember that polyphenols are antioxidants, and catechins, as discussed, are one of the most powerful. Many clinical studies use therapeutic dosages to test them out, but when you ingest the actual food or drink — in this case, green tea — you also get benefits.
Regarding EGCG content in different teas per cup, Acne Einstein noted that many studies used therapeutic dosages of 300 milligrams (mg) to 1,000 mg per day.
In comparison, analyzing the list of teas on the U.S. Department of Agriculture (USDA) website7 in relation to the highest flavonoid content, brewed green tea outstrips any other type easily with 180 mg of EGCG content per cup. The decaffeinated version offers just 60 mg, while bottled green tea has just 10 mg.8
One study showed that one-half cup of green tea presents the same antioxidant potential as 1 kilogram — nearly 2.5 pounds — of fresh fruit.9
Studies on Green Tea and Remarkable Benefits
Epidemiological studies indicate that people who drink six or more cups of green tea a day have lower levels of damage from inflammation, even DNA damage. In fact, the Mount Sinai Health System lists numerous health benefits from green tea consumption:
"Preliminary studies suggest that drinking green tea can help prevent dental cavities … Green tea may also be useful in inflammatory diseases, such as arthritis. Research suggests that green tea may help arthritis by reducing inflammation and slowing the breakdown of cartilage.
Chemicals in green tea may help treat genital warts, treat dermatologic conditions, and prevent symptoms of colds and flu. Green tea may play a role in preventing Parkinson’s disease, cognitive decline and osteoporosis. Studies also show that drinking green tea is associated with reduced risk of dying from any cause."10
In China and India, people drink green tea to get rid of excess bodily fluid, control bleeding, heal wounds and improve their heart health. Green tea is also used to regulate blood sugar levels, improve mental clarity and promote digestion. Studies reported a number of other benefits, including cancer inhibition:
Atherosclerosis, as studies show green tea consumption reduces heart disease risk by lowering triglyceride levels11
Weight loss, by boosting metabolism and burning fat12
Skin cancer, as EGCG polyphenols have anticancer and anti-inflammatory properties that may help prevent the development of skin tumors13
Stomach cancer, as researchers found green tea drinkers were about half as likely to develop stomach cancer and inflammation14
Bladder cancer, as women who drank green tea were less likely to develop bladder cancer and kidney cancer15
Ovarian cancer, as patients experienced decreased occurrence rates16
Breast cancer, as researchers found that women who drank the most green tea had a 22% lower risk17
Esophageal cancer, as animal studies have found that green tea polyphenols inhibit esophageal cancer cell growth18
Colorectal cancer, as studies show regular green tea consumption may reduce colorectal cancer risk in women by 57%19
Pancreatic cancer, as a large clinical study found that those drinking the most green tea were less likely to develop pancreatic cancer20
Prostate cancer, as men who drink green tea have a 48% lower risk21
Lung cancer, as green tea polyphenols have been shown to inhibit the growth of human lung cancer cells in test tubes
Inflammatory bowel disease, as green tea may reduce inflammation associated with Crohn's disease and ulcerative colitis22
Liver disease, as catechins may help treat viral hepatitis, a type of liver inflammation23
Diabetes, helping to prevent Type 1 from developing and slowing progression24
Did You Know? Green Tea Fights Acne
People who struggle with acne have more systematic inflammation than is common,25 but once again, drinking green tea has been found to be very beneficial. Anecdotal evidence — in short, people who noticed improvement and reported it — has been very encouraging.
Studies have shown that people with severe acne had more problems with inflammation and fewer antioxidants than those with mild acne. One study comments that "the notion that lipid peroxidation is a 'starter gun' in acne is not a new one."26
Inflammation of this order can come from a number of sources, but several to pay close attention to include gut health (or lack thereof), getting inadequate sleep and high levels of stress. Without a doubt, people with acne should consider what they eat in relation to their skin problems, as more than one study has explored acne being due to consuming unhealthy foods.27
There must be something to be said about the fact that in many indigenous societies, acne is virtually unheard of, while in so-called "enlightened" populations, it's a big problem. The above study noted:
"How could we ever rule out the possibility that diet has no effect on acne? Especially when diet influences the absorption of a nutrient or a drug that affects the mitigation of that disease? Maybe we cannot treat acne with nutrition but we can certainly influence it."28
Time, Type and Temperature Makes a Difference in Tea-Brewing
Between the three main varieties of tea — green, black and oolong — how the tea leaves are processed makes all the difference. Then there's white tea, which researchers believe may have similar health characteristics compared to green tea.29
Matcha tea, which means "powdered tea," is authentically green, but possesses several other differences that set it apart. While regular green tea involves soaking the leaves, either loose or in a bag and pitching them, matcha green tea is the actual leaves, ground micron fine. Acne Einstein cites the findings in a U.K. study30 and explains:
"… [W]hen you make tea using tea bags you'll get significantly less EGCG than from loose leaf and powdered teas. The authors speculated that this could be because the tea bag itself prevents some EGCG from being absorbed. Or, more likely, that tea bag contains lower quality leaves."31
Say you decided to prepare a cup of green tea and heated the water to less than boiling, then steeped your grocery store teabag for less than a minute. A study revealed that in comparison, using high-quality, loose-leaf tea and brewing it in boiling water increases the antioxidant potential.32
According to one study, the hotter the water you brew your loose-leaf tea in, the more antioxidants you can expect to benefit your body. Further, the EGCG extraction is particularly sensitive to water temperature; brewing water in 80 degrees Celsius, or 176 degrees Fahrenheit, imparts only about 60% of the ECGC from the tea leaf.33
The best amounts to use when measuring loose-leaf tea is a ratio of 4 teaspoons of tea for every 4 cups of water. Drink it while it's hot; freshly brewed tea is also superior to tea that's been sitting for a few hours. Further, as an FYI, adding milk can diminish the potency of some of the antioxidants, while adding a spritz of lemon can boost the green tea benefits and increases the catechins for better absorption by five times, one study shows.34
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Research in people with a range of heart disease risk factors has shown that consuming green tea extract for four weeks can lower blood sugar levels and improve gut health by decreasing inflammation and reducing "gut permeable".
"There is a lot of evidence that greater consumption of green tea is associated with good levels of cholesterol, glucose and triglycerides, but no study has linked its benefits in the intestine with these health factors," says Richard Bruno, lead author of the study and professor of human nutrition at Ohio State University (United States).
"This absorption of products derived from the intestine is believed to be a factor initiating obesity and insulin resistance, which are fundamental to all cardiometabolic disorders. If we can improve the integrity of the intestine and reduce intestinal leaks, the idea is that we will be able to not only alleviate the low-grade inflammation that initiates cardiometabolic disorders, but potentially reverse them.
https://www.sciencedaily.com/releases/2022/07/220726132640.htm (2022).---
https://academic.oup.com/cdn/article/6/Supplement_1/981/6606956 (2022).----
https://apcz.umk.pl/JEHS/article/view/45192 (2023)
https://www.taylorfrancis.com/chapters/edit/10.1201/9781003369813-4/flavonoids-cardiovascular-diseases-lovlish-gupta-monika-chauhan-ajay-kumar-diwakar-chauhan-pragati-saini (2024)
Green tea is a widely used drink with healthy effects on several diseases, including cancer. The bioactive compounds in green tea are mainly catechins, and epigallocatechin gallate (EGCG) is the most abundant and biologically active among them. In this review, we present evidence for the modulation of autophagy and anticancer effects induced by EGCG treatment in experimental cancer models. The reviewed articles reveal that EGCG promotes cytotoxic autophagy often by inactivating the PI3K/Akt/mTOR pathway, resulting in the induction of apoptosis.
The selected studies rightly claim that EGCG is a valuable agent in cancer chemoprevention. There is increasing evidence showing that many flavonoid-rich fruits, teas or herbs contain molecules that express anti-cancer properties by regulating cell fate through autophagy and apoptosis. Among them, epigallocatechin gallate (EGCG), from green tea extract, has been in the spotlight for years, and its potential as an antioxidant, anti-inflammatory and anticancer agent has been widely described. In preclinical studies involving different tumor cell lines, a wide range of molecular mechanisms have been attributed to EGCG, affecting cell proliferation, apoptosis, and autophagy pathways. The polyphenol fraction can represent up to 40% of the dry mass of fresh leaves. Together with methylxanthines, L-theanine, tannins, gallic acid and vitamins, phenolic compounds constitute a set of bioactive molecules with a potential impact on humans. Among these bioactive compounds, flavonoids represent the most frequent component, mainly due to the content of catechins. Epigallocatechin gallic acid ester is definitely the main component of green tea catechins. In fact, it represents between 50% and 80% of total catechins. These compounds are considered responsible for several health-promoting properties of green tea. These health effects range from antioxidant/prooxidant, antineurodegenerative, antimicrobial, and antidiabetic activity to anticancer activity. Additionally, synergistic anticancer effects should be considered when green tea catechins are combined with other natural compounds rich in antioxidants.
https://www.mdpi.com/1422-0067/23/11/6075 (2022).----
https://www.mdpi.com/1420-3049/28/5/2151 (2023)
https://www.sciencedirect.com/science/article/pii/S1756464623005777 (2024)