While
nobody is running around extolling the virtues of cola as a replacement for
water for daily hydration, researchers at Kings College London want … Read…
Tea
isn't just a comforting and pleasant beverage, it also has remarkable healing
properties—so much so that it's deemed a sort of "wonder drink" that
may be even healthier
than drinking water. Here are all the ways drinking tea can lead to
a healthier, longer life—and how to maximize both the enjoyment of the drink
and its health benefits.
Not Just
for Pleasure: The Many Health Benefits of Tea
What
are these tablet dealies?
Tea is
the second most
widely consumed beverage in the world, after water. That's because
it's so versatile: You can drink it iced or hot, and there are enough varieties
of tea to suit just about any palate (there are over 1,500 types of
tea—not including herbal teas).
No.
It's because you have to boil water to have tea, thus negating any water born
illness in the beverage.
People
have been drinking tea for centuries also because of its health effects. Much
research suggests drinking tea—particularly green tea—can fight diseases and
even lengthen life. This is due to tea's high concentration of antioxidants
called polyphenols, which may contribute
to the prevention of cancer, osteoporosis, and cardiovascular diseases.
While polyphenols are also found in abundance in fruits, vegetables, and
grains—and also coffee in even higher amounts—tea is especially and uniquely
rich in particular types of polyphenols called catechins (specifically, EGCG) that may be the most powerful ones of all.
Cancer
Prevention
The
American Cancer Society explains:
EGCG may help cause
certain types of cancer cells to die in much the same way that normal cells do.
This effect is important because cancer cells are different from normal cells
in that they do not die when they should—they continue to grow and spread.
Although
the ACS says more clinical trials are needed to support claims that green tea
can prevent or treat any specific types of cancer, it notes the many laboratory
studies demonstrating green tea's protective effects against cancer cells. One
study, for example, found EGCG to suppress lung cancer cell growth and another found that it inhibits breast
cancer tumors. A meta-analysis of
13 studies indicates women who drink green tea have a lower risk of
developing breast cancer than non-green-tea drinkers. Like most scientific
research, however, there's other conflicting results suggesting black and green
tea might not contribute significantly to breast cancer risk—so
you probably shouldn't drink tea for the sole purpose of preventing cancer.
That's okay, because there are lots of other positive health associations with
tea.
Protection
Against Heart Diseases and High Blood Pressure
A study of 40,530
people in Japan, where green tea is widely consumed, found drinking
green tea significantly lowered the risk of dying from cardiovascular disease.
(31% lower risk in women, and 22% lower risk in men.) The risk of dying from
stroke was even lower: 62% lower in women and 42% lower in men. The catechins
in green tea are believed to inhibit the production of free radicals in the
lining of the arteries and also help prevent the formation of blood clots.
Regular
consumption of green or oolong tea (for at least one year) also has been shown
to lower the risk of developing hypertension by 46% for those who drank up to
2.5 cups a day and 65% less for those who drank more than 2.5 cups.
A
review, published in the Journal of the American College of Nutrition, concludes that "green tea and EGCG can be regarded as
food components useful for the maintenance of cardiovascular and metabolic
health."
Lower
Risk of Death from All Causes
The
Japanese cohort study mentioned above examined the relationship between green
tea drinking and death from all causes. The researchers followed the Japanese
adults (ages 40 to 79) for up to 11 years and compared those who drank less
than one cup of green tea a day to those drinking five or more a day.
The
results? Drinking green tea was associated with a 23% lower risk of dying from
any cause in women and 12% lower risk in men.3
I
mostly drink tea so I won't die in a car accident.
Brain
Boosts
Drinking
tea can contribute to both relaxation and concentration. As Tea Class explains:
L-theanine
is an amino acid that occurs naturally in the Camellia Sinensis plant. In fact,
unless you take an artificially manufactured dietary supplement, tea is the
ONLY way to get L-theanine in your diet. This powerful amino acid boosts alpha
wave activity in our brains, which promotes a state of relaxed concentration.
Think "quiet alertness". The calming effects of L-theanine actually
counteract the extreme highs and jitteriness that can result from excessive
Caffeine intake.
As with almost all other
essential elements in the leaf, L-theanine is most highly concentrated in the
newest growth. A high quality loose leaf tea will contain the most L-theanine,
and the very highest levels are usually found in green and white teas.
And Lots,
Lots More
Studies
have also associated drinking green tea with lower LDL or
"bad" cholesterol and reduced body fat, inhibition of
the flu virus, and even less dental
plaque. The book Green Tea by Nadine Taylor also cites these
benefits:
·
Keeping blood sugar at moderate levels
·
Fighting food-borne bacteria
·
Enhancing immune system function
·
Promoting "friendly" bacteria in the intestines and
encouraging bowel regularity
·
Assisting in weight loss by blocking the breakdown of starch
·
Maintaining the body's fluid balance
·
Reducing stress
Taylor
writes:
No other substance on the
face of the earth, including the most potent drug, can claim such wide-ranging
and powerful health benefits, and all without a single side effect.P
Well, some side
effects have been noted with drinking too much green tea extract or
supplements (not the drink itself), and pregnant women might want to avoid
large amounts of green tea as well.
For all
of its wild popularity, caffeine is one seriously misunderstood substance. It's
not a simple upper, and it works differently on… Read…
It's
true that tea contains caffeine, which affects everyone
differently, but tea generally contains less caffeine than coffee,
and the caffeine in tea is metabolized more slowly, so you can drink more cups all day
long without crashing.
How to
Choose and Brew Tea for Better Health Benefits
Now
that we know some of the many potential ways green tea can make us healthier,
let's look at how to buy and brew it optimally.
Types
of Tea: Most of the studies have focused on the health benefits of green
tea, but what about black and other types of tea? Green tea has more
wide-ranging and powerful benefits mainly because of its high amounts of EGCG,
whereas black tea has much less because of the way the leaves are
"fired" and oxidized during production. Still, black and other teas
also share these important compounds and benefits.
Acne Einstein
reports these mean levels of EGCG in different teas per cup, as measured by the
USDA:
·
Brewed green tea: 180mg
·
Brewed green tea, decaffeinated: 60mg
·
Brewed green tea, flavored: 45mg
·
Ready-to-drink green tea: 10mg
·
Brewed oolong tea: 80mg
·
Brewed black tea: 20mg
The
report doesn't mention white tea, which has similar EGCG content as green tea,
but might have even more health benefits than green tea because it's even less
processed. White tea, however, is rarer than green and thus less studied.
Antioxident
content, however, also varies depending on the tea types, brand, and
manufacturing.
Tea
Brands: Speaking of tea brands, ConsumerLab tested green tea bottled drinks, brewable teas,
and supplements to find which had the highest levels of EGCG and other
catechins. News Observer reports:
Of the
14 bottled tea and tea supplements that listed levels of EGCG on the label,
only three contained significantly less than the amount claimed. The 17-ounce
bottle of Honest Tea Green Tea with Honey, for example, had only about
two-thirds of the 190 milligrams of the listed catechins, which includes EGCG
and other beneficial compounds. (Experts recommend consuming 200 milligrams of
EGCG a day for the greatest benefit.)
Among products that don't
list EGCG levels – including all of the brewed teas – findings were more
varied. Teavana Green Tea Gyokuro Imperial, sold as loose tea, had 86
milligrams of EGCG per serving, while one bag of Bigelow Green Tea had only 25
milligrams. To get the recommended amount of EGCG, you'd have to drink about 2
1/2 cups of the former, eight cups of the latter. (Helpful hint: Steep tea in
hot water for three to five minutes to fully extract the EGCG.)
Teavana's
is more expensive, however ($2.18 to get the equivalent of 200 mg of EGCG
versus $0.27 to $0.60 per tea bag). Bigelow's had the highest amount of EGCG of
the bagged, supermarket teas.
There's
a lot to love about tea. It's soothing but can give you a boost, available in
different varieties, and it's easy to make--for… Read…
Temperature
and Brewing Time: Things that additionally affect the EGCG content and
antioxidant potential include your water temperature and brewing time. While
following general time and
temperature recommendations is great for brewing a cup of tea for
flavor, if you care about getting the most health-boosting benefits of a cup of
tea, Acne Einstein has found.
·
Brewing with hotter water results in more antioxidants in the
tea
·
Steeping for three to five minutes is better than less time
This
goes against the usual tea rules for different types (green tea is usually
brewed with water at 175 degrees F and for just a minute or so), so you might
get a stronger-tasting or even bitter cup, depending on the leaves. Oolong
teas, however, often do well with longer steeping time and higher temperatures.
How
Many Cups to Drink a Day: Most of the studies suggest the more cups of
tea you drink a day (e.g., five or more), the better, but some also found
benefits with just two to three cups a day, which is what nurse practitioner
and physician assistants network Advanced Healthcare recommends for patients as a "simple
healthy lifestyle strategy." (Don't worry, tea is hydrating and doesn't
act as a diuretic.) The two-to-three cups a day recommendation fits in with
most supplements' 200 mg EGCG recommended daily serving.
Coffee
is great, but even die-hard coffee lovers might want to give tea a chance. The
other beloved warm beverage, tea imparts to its drinkers some… Read…
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