Green tea benefits
Health Benefits of Japanese Tea

The Incredible Health Benefits of Drinking Japanese Green Tea

Only within the last 30 year has scientific research given credibility to what tea drinkers around the world have known for centuries….green tea benefits your health, it is good for you! It is nature’s gift, a simple but extremely effective way to promote human health. Since green tea has little caffeine and is one of the mildest of the teas, there are no adverse side effects either.


Tea is the most widely consumed beverage in the world next to water, consumed daily by over two-thirds of the world’s population. The plant Camelia Sinensis yields a variety of tea types which include black, green and Oolong. Incredibly, three billion kilograms of tea is produced and consumed yearly. This breaks down to approximately 78% black tea, which is usually consumed in Western countries, 20% green tea, which is commonly consumed in Asian countries, and 2% is Oolong tea which is produced (by partial fermentation) mainly in southern China (Khan and Mukhtar, 2007).

Although all teas can be beneficial to health, and all teas derive from the same plant (Camelia Sinensis) they differ in their appearance, taste, flavour, and chemical content. This is due to their fermentation process. It is the green tea benefits we are most interested in and there is a reason for that. It is the most potent and beneficial.

green tea

Green Tea is prepared using unfermented leaves

Oolong Tea

Oolong Tea is prepared using partially fermented leaves

Black Tea

Black Tea is prepared using fully fermented leaves

The Chemical Constituents of Tea

The chemical components of tea leaves include polyphenols (catechins and flavonoids), alkaloids (caffeine, theobromine, theophylline, etc.), volatile oils, polysaccharides, amino acids, lipids, vitamins (e.g., vitamin C), inorganic elements (e.g., aluminium, fluorine and manganese) (Sharangi, 2008).

It is the polyphenols that interest us. These are the components primarily responsible for the health benefits of tea. Flavonoids are responsible for providing anti-inflammatory, antioxidant, anti-allergic and anti-microbial effects. The isomers of flavanol are: catechin, catechin gallate (Cg), gallocatechin, gallocatechin gallate (GCg), epicatechin, epicatechin gallate (ECg), epigallocatechin, and epigallocatechin gallate (EGCg) (Nagao et al., 2005).

The polyphenol content of green and black tea varies greatly, with green tea containing 30% to 40% polyphenols and black tea around 3% to 10%. So it is green tea consumption which is the more beneficial and the products that likes to provide.

The Health benefits associated with Japanese green tea consumption

Green tea benefits: Acts as an Antioxidant

It’s the polyphenols in green tea which scientists believe may provide potent antioxidant effects (Hara, 2001). Antioxidants may also have health benefits in the prevention of cancer (Mitscher et. al., 1997). When using the oxygen radical absorbance capacity, green tea was found to have a greater antioxidant activity than Brussels sprouts, garlic, kale and spinach.

Green tea benefits: fights against various forms of cancer

The cancer-protective effects of green tea have been reported in several population based studies. For example, cancer rates tend to be low in countries such as Japan where green tea is regularly consumed. It is not possible to determine from these population- based studies whether green tea actually prevents cancer in people. However, emerging animal and clinical studies are beginning to suggest that EGCg may play an important role in the prevention of cancer. It has been suggested that EGCg and other tea catechins suppress tumour promotion by inhibiting the release of tumour necrosis factor-alpha, which is believed to stimulate tumour promotion and progression of initiated cells as well as premalignant cells (Fujiki et. al., 2003).

Green tea benefits: consumption reduces the risk of cardiovascular disease

Hypertension is a major risk factor for the development of cardiovascular diseases and the consumption of green tea has been shown to reduce blood pressure and help prevent strokes and heart disease. Green tea may also help reduce cholesterol. The continuous “ingestion of a green tea extract high in catechins led to a reduction in body fat, SBP, and LDL cholesterol, suggesting that the ingestion of such an extract contributes to a decrease in obesity and cardiovascular disease risks of human beings” (Nagao, Hase, & Tokimitsu, 2007).

Green tea benefits: can help prevent diabetes

While green tea has been recognised as a traditional remedy for controlling blood sugar levels, a study by Waltner et. al., 2002 showed that it may indeed help to prevent the development of type 1 diabetes and slow its progression once it has developed. EGCg has been found to increase insulin sensitivity and may repair damaged beta cells (McKay & Blumberg, 2002) (Koyama et. al., 2004) (Anderson & Polansky, 2002).

Green tea benefits: aids in indigestion

Green tea contains astringent tannin compounds which can help to ease various digestive problems.

Green tea benefits: can Improve oral health

The tea plant Camelia Sinensis extracts fluoride from the soil which accumulates in the leaves. One cup of green tea may contain 0.3 to 0.5mg of fluoride which has strong binding properties to the tooth enamel helping prevent tooth decay (Sharangi, 2009).

Green tea benefits: helps prevent liver disease

The liver’s antioxidant supply can be boosted by green tea consumption, helping to fight the free radicals produced by alcohol consumption (Ostrowska et. al., 2004).

Green tea benefits: boosts the immune system

For the body to be able to heal itself the immune system needs to become stronger. Green tea nutrients help to strengthen the immune system through its ability to capture free radicals, invigorate, detoxify, along with teas natural antibacterial properties.

Green tea benefits: boosts cognitive function

Theanine allows the brain to better focus and problem solve with increased levels of concentration. Studies on rodents have shown that the ability to learn and remember may be enhanced with theanine supplementation. This natural relaxant works to diminish stress, worry, and anxiety, and may allow the brain to focus and concentrate better (Huber, 2003) (Kakuda et. al., 2000) (Yokogoshi, 2000).

Green tea benefits: treats arthritis

Laboratory studies have found that the polyphenolic fraction isolated from green tea has been reported to possess anti-inflammatory properties in laboratory animals, with a significant reduction in the incidence of arthritis. An experiment involving mice exhibited a significant reduction in the incidence of arthritis (33%) compared with mice not given green tea polyphenols (50%). Analysis showed a marked reduction in the expression of inflammatory mediators such as cyclooxygenase 2, interferon (IFN)-_, and tumour necrosis factor (TNF)-_ in the arthritic joints of the mice fed green tea polyphenols. (Haggi et al., 1999).  

Green tea benefits: can help to reduce obesity and burn fat

The basic definition of obesity is the imbalance between energy intake and energy expenditure. It is a metabolic disorder. It is also a strong risk factor for other lifestyle-related diseases. A study (Murase et al., 2006) investigated the effects of the long term intake of green tea catechins when combined with regular exercise and how it affects the obesity levels of laboratory mice. The results indicated that tea catechins boosted the metabolism which helps to burn fat. In another study (Dulloo, 1999) showed the metabolic rate increased by 4% after 90mg of EGCg was consumed three times a day in human test subjects. Westerterp-Plantenga et al., carried out another animal study in 2005 involving EGCg which caused rats to lose 21% of their body weight. When EGCg was injected it caused rats to lose their appetite, in turn consuming up to 60% less food. This occurred after 7 days of daily injections. It is thought EGCg desensitize leptin receptors (leptin may play a role in appetite) (Yung-Hsi K et. al., 2000).

Green tea benefits: reduces stress

The calming effects of green tea are one of the reasons that its consumption has been encouraged for centuries in eastern cultures. This is a natural relaxant which may help lower levels of anxiety and reduce stress. The presence of L-thenanine is the amino acid responsible for producing the tranquilizing effects in the brain. Three to four cups of green tea may contain 60 to 160mg of theanine (Talbott, 2002) (Huber, 2003). Theanine is believed to lower cortisol levels during stress periods (cortisol production in the body increases during physical stress). Research has also found that the brains output of alpha waves is increased by L-thenanine. Research studies have found that people who produce more alpha brain waves also have less anxiety and highly creative people generate more alpha waves when faced with a problem to solve.

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