So wrote the Buddhist monk Eisai in "Kissa-yojo-ki (Tea Drinking for the Cultivation of Life, above)" in the 13th century. He brought back the custom of drinking powdered tea to Japan from China.

In Asia, particularly in China, various effects of tea have been known since ancient times, but it was in the Western countries that effects of specific ingredients in tea were brought to light for the first time; tea caffeine was discovered in 1828 and tannin in 1848.

In Japan, studies on the ingredients in green tea began in the 1920s. As interest in their effects on health increased, extensive studies including animal experiments to investigate the physiological effects of green tea were begun in the 1980s.

These studies have revealed that green tea contains many beneficial substances for health, especially catechin, in addition to caffeine and vitamins A, C and E.

Various adult diseases are spreading into younger generation these days due to changes in life styles and eating habits. Catechin is considered effective for:

Cholesterol is a fatty substance in tissue which is essential to health. However, the rise of cholesterol density above the normal level in blood could be a risky factor in arteriosclerosis*. Catechin is considered effective in inhibiting the absorption of excessive cholesterol and in balancing the level of cholesterol in the blood by maintaining HDL (high-density lipoprotein) and decreasing LDL (low-density lipoprotein)**.

*narrowing of the arteries because of fatty deposits, which can precipitate heart diseases, stroke and other cardiovascular diseases
**The HDL is considered to be a "good" cholesterol, helping remove cholesterol from tissues while LDL is a "bad" cholesterol, being a primary cause of heart attacks.

-inhibiting platelet agglutination*

*a reaction in which platelets collect into lumps

Platelets are disc-like structures in blood that help stop bleeding by forming plugs. On the other hand, cerebral and myocardinal infractions are triggered by agglutination. Catechin is considered effective for inhibiting excessive collection of platelets in blood.

High blood pressure is not only a serious condition by itself, but it is also the leading cause of heart attacks, strokes, and kidney failure.

The causes of high blood pressure are not yet fully understood, but it is clear that an enzyme (called renin), secreted by the kidney, causes the formation of a chemical substance (called angiotensin), which raises the blood pressure by causing the blood vessels to become narrower. Catechin is considered effective in inhibiting excessive activations of the enzyme and lowering the blood pressure accordingly.

Diabetes is a common but serious disease, leading to serious complications. It may cause changes in the blood vessels of the retina and the kidneys, and, in advanced stages, it becomes a major cause of blindness.

It is said that diabetes cannot be cured but proper treatment can improve a patient's condition considerably. The body of a diabetic person is slow to use sugar (glucose), and so sugar builds up in the blood, due mainly to a lack of the hormone insulin*, raising blood-sugar levels as a result.

*Insulin, which is produced by the pancreas, enables the body to use and store sugar quickly.

Catechin is considered effective in inhibiting sudden rises in blood-sugar levels. It is considered that catechin inhibits or delays the digestion and absorption of starches and sugars in the small intestine.

Catechin is said to prevent food poisoning caused by such bacteria as staphylococcuses, botulinuses and enteritis vibrios. Catechin has effects on germs, but it does not harm such beneficial bacteria for health as lactobacillus bifidus*, and, furthermore, it helps them increase, while it inhibits the increase of harmful bacteria, both in the same intestines.

*Lactobacillus bifidus breaks down sugars into lactic and other acids.

*Sashimi is fresh seafood fillets cut into bite-sized pieces, which are eaten raw with soy sauce.

Hot green tea is usually served with sashimi or sushi*, which can easily spoil. Is this a natural way of preventing food poisoning?

*vinegared rice topped or combined with sashimi and other items

Catechin is also said to have the ability to prevent dental decay* and plaque formation.

*Fluorine in green tea also plays a part too.

One special anti-virus effect of catechin is the prevention of influenza. Gargling with green tea is recommended by some doctors.

An allergy is a physical reaction that occurs in persons who are sensitive to certain substances*.

*These substances are called allergens. Not only house dust and pollen but also foods and such additives as preservatives are allergens.

Common forms of allergy include asthma, hey fever and sinus allergies. Others are itchy red swellings on the skin (eczema) and allergic headaches. The allergens, together with proteins called anti-bodies, act to release such substances as histamine from the body cells into the blood and other body fluids. These substances can cause allergic reactions.

Catechin is considered effective in inhibiting histamine from being released into the blood and other fluids, thus relieving the various allergic symptoms.

Tea began as a medicine in ancient times in China. About 1,200 years ago the custom of drinking tea was first introduced into Japan from China. Since then, various teas brought from China have developed into a uniquely Japanese green tea.

Sencha green tea has taken root as an everyday beverage in Japanese life, but, since coffee, cola and other drinks have become popular, the consumption of green tea has decreased significantly over the past 40 years.

However, with the catechin in tea highlighted for its medicinal value, many people have now started appreciating the true value of green tea as a rare beverage which brings relief to both body and mind.