It has been consumed for over 4,000 years across Asia and is commonly believed to be a synonym for tea plant; but, what is green tea exactly? The truth is that green tea is one of the many types of tea derived from the leaves and buds of the Asian evergreen.
In order to avoid oxidation, maintain color, and preserve essential compounds, the tea leaves are harvested in early spring and spread outdoors before being steamed or heated. The steamed green tea is consumed mostly in Japan while the fried-panned green tea is mainly produced in China and exported to the rest of the world.
Types of Green Tea
According to the area where the tea plant is processed, the range of green shades, flavors, and scents vary. Therefore, different types of green tea are available.
Dragonwell green tea. This is a well-known Chinese tea, which possesses a vivid green color along with a sharp taste and earthy aroma. When steeped, its leaves open, showing the buds within.
Sencha green tea. This is the most consumed Japanese tea. Slightly astringent with a hint of sweetness, it accounts for approximately 75% of the tea production in Japan.
Genmaicha green tea. This is a Japanese blend of green tea and fire-roasted rice with a mild, toasty taste and a bristly texture.
Gyokuro green tea. Also from Japan, it is similar to Sencha but slightly darker with pine-needle-like leaves and a mildly sweet taste.
Green tea in India and Ceylon green tea (Sri Lanka) are of little commercial relevance since both countries produce a high quality selection of black teas.
Health Benefits of Green Tea
The health benefits of green tea exceed the ones provided by Oolong and other dark types of tea. The Chinese and Japanese have been reaping its medicinal properties for millennia, and modern science has found green tea particularly useful for:
Boosting metabolism. Green tea can help dieters achieve their goals and maintain a healthy weight with an additional stimulating effect, similar to coffee.
Reducing cholesterol. The consumption of green tea has been associated with a reduction of low-density lipoprotein (LDL), or “bad cholesterol.”
Lowering blood pressure. Green tea can help reduce blood pressure, thus reducing the risk of stroke and coronary heart disease.
Preventing degenerative diseases. Green tea has been shown to restore cellular function in patients with Alzheimer's disease.
Additionally, green tea has proven effective against oral and intestinal bacteria, which means that it may help prevent tooth decay and treat diarrhea.
Green Tea Caffeine Content
The level of caffeine in green tea depends on the amount used and the length of time the leaves are steeped. An eight-ounce cup of green tea contains about 15 mg of caffeine, while brewed coffee provides 80 - 135 mg per cup.
Drinking green tea as little as twice a day has shown to improve energy and metabolic functions; moreover, green tea supplements can provide the same health benefits.
Those who are sensitive to caffeine have many options of decaf green tea products to choose from in order to reap its antioxidant benefits.
Green Tea Antioxidants
The major green tea antioxidant compounds are polyphenols, including phenolic acids and catechins, particularly epigallocatechin gallate (EGCG), to which most benefits of green tea can be attributed. By regulating cellular functions, improving blood circulation, and speeding up metabolism, the EGCG in green tea supports cardiovascular health and promotes weight loss.
Green Tea Diet
The market of dieter's tea is wide and diverse. However, claims of green tea diet being the best one for weight loss may not be so far-fetched.
Along with a workout program and a nutritional plan, taking green tea capsules or drinking green tea after every meal can help improve metabolic rate in order to get rid of those extra pounds and maintain a healthy weight.
Green Tea Side Effects
While drinking green tea in moderation is generally considered safe, liver toxicity has been associated with the intake of weight loss supplements containing green tea extract.
Green tea may also lower the absorption of iron and folate. This and other undesirable green tea effects, such as insomnia, headaches, and even diarrhea, are directly related to overconsumption.
How to Make Green Tea
Brewing green tea is quite simple, but quality green tea is a must for better taste. A teaspoon of green tea leaves in one cup of water just below boiling temperature is enough to obtain an invigorating infusion.
It is important to give the leaves enough time to release their rich flavor and aromatic scent. After ten minutes, the preparation can be strained. No milk should be added to a green tea drink. Instead, lemon and honey are good choices for extra taste.
Green Tea Price
The price of green tea depends on its quality and processing. One of the advantages of green tea is that it is available in different forms, from bulk green tea to green tea power (popularly known as matcha tea), including a variety of green tea supplements.
While it is commonly found in supermarkets and organic stores, the easiest way to purchase green tea is online, where prices range from around $6 USD for pure green tea bags or capsules to nearly $19 USD for green tea powder.
When it comes to high quality green teas, the price of a fine Gyokuro green tea ranges $48 - 487 USD, and a premium Sencha green tea can be purchased for $48 - 162 USD.
Sources
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- International Journal of Obesity, The effects of green tea on weight loss and weight maintenance: a meta-analysis, 2009
- Nutrients, Epigallocatechin Gallate (EGCG) Is the Most Effective Cancer Chemopreventive Polyphenol in Green Tea, 2012
- Physiology & Behavior, Green tea catechins, caffeine and body-weight regulation, 2010
- Side Effects of Drugs Annual, p. 597
- Tea and Tea Products: Chemistry and Health-Promoting Properties, p. 3
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- University of Rochester Medical Center, Green Tea Extract
- University of Utah, Caffeine Content Of Popular Drinks
- Journal of Alzheimer's Disease, Green tea epigallocatechin-3-gallate (EGCG) and other flavonoids reduce Alzheimer's amyloid-induced mitochondrial dysfunction, 2011