Connections between drinking TEA and HEALTH1. Introduction to the history of taking tea
Enjoying tea prevents diseases, preserves health and prolongs life. In China people have this beneficial habit since a long time. Lu Yu from the Tang-Dynasty (AD 618-907) wrote the Classical tome about tea (Cha Jing) which had him risen to immortal honor as the "Tea God" deified by the tea vendors. Because of this, some people assume the habit of taking tea stems from that period of time, but in fact tea leaves were already used as medical herbs in very early times: A description in the Shen Nong Materia Medica (Shen nong ben cao) compiled from classical sources at the western Han-Dynasty (BC 206-5 AD) comments: "Bitter-cool in taste... when often used gives a feeling of satisfaction and a calm mind, raises the spirit and makes life lasting." Also in the Shen Nong Dietetics Classic (Shen nong shi jing) it is emphasized: "Tea leaves promote diuresis, drive out phlegm and heat, stop diarrhea and help people to sleep less..." and "Taking often tea gives people strength, joy and perseverance."
2. Taste and functions of tea
Taste: bitter-sweet, cooling character
Function: A. Helps digestion, dispels heat, refreshes the spirit, clears the eyes,
promotes concentration and relaxation, dissolves fat, expels "summer-
heat" (shu), stops diarrhea, assists diuresis and detoxification .
B. Tea leaves contain fragrant etheric oils which stimulate the
incretion of the stomach fluids, help digestion ( bowel movement ),
increase appetite and rinse out the accumulated sediments in the
C. According to ancient belief it is said in the Shen Nongs 100
appreciated herbs that we daily absorb 712 sorts of poison, of which
only tea is able to dissolve them.
D. It can reduce and prevent the production of cancer cells. People
living in typical tea plantages are found to have an extraordinary low
rate of cancer.
E. For old people with "vacuity" symptoms in kidneys and spleen,
dizziness, bad eyesight and diminishing memory it is highly
recommendable to drink often tea, since this helps to digest fats, raises
the spirits, dispels "fire", clears the eyesight and calms the mind and
improves the mood. Drinking tea regularly in the summertime prevents
and cures enteritis and summer-diarrhea.
F. Since it contains the vitamins C and P, tea increases also the
flexibility of the blood vessels' walls, which helps to prevent artero-
sclerosis, cerebro-vascular diseases, etc. and has multifarious other
3. Analysis of the ingredients found in the tea leave
and their pharmaceutical application
Pharmaceutical research has analyzed all components found in the tea leaves among others there are fragrant aromatic oils, coffeine, alkalic minerals (manganite), tannic acid, vitamins (A,B2,C,D and P).
The aromatic oils exite the nerves of the cerebro-vascular (brain-blood vessels) system and increase the oxygen absorption and transport, which raises the spirit and euphorizes the mood.
Coffeine expands the blood vessels and stimulates the forebrain, adjusts the stomachs secretion, increases the kidneys diuresis and promotes the detoxification process in the liver.
The alkaline mineral in the green and brown tea (manganite is destroyed by complete fermentation and hence not found in black tea), enlarge the fat digestion, a function which -in cooperation with the coffeine's functions- stop the raising of the puric acid (purine) to prevent gout and prevent as well as treat the myocard infarcts of the heart.
Tannic acid is an astringent antilaxans (stops diarrhea), also helps with fat digestion, is antiseptic (destroys some bacteria) and plays a role in the livers detoxification of alkaloid poisons.
Furthermore tea contains some nourishing components like sugars, proteins, amino-acids, vitamins and some mineral trace-elements like copper, fluor, iron, aluminum, magnesium, zinc, strontium, calcium, magnesium etc.
Recently scientists have moreover discovered that people living in tea cultivation areas suffer extraordinarily seldom from cancers and infarcts. Tea leaves -so the conclusion- must contain factors that control and inhibit the production of cancer cells. If tea leaves are added to the daily diet of white laboratory rats, their cancer cells are remarkably reduced or even extinguished after just three weeks.
4. Differentiation of tea sorts
Tea leaves are distinguished by their preparation and the different tea leaves, in general, we can divide them into four major classes:
1. Green Tea- unfermented
2. Oolong (Wulong) Tea- semi-fermented
3. Black Tea- completely fermented
4. Pressed Tea (tea bricks)- only used in a few areas, often as medicament
From the viewpoint of TC medicine, green tea is cool in character and has better abilities for cooling "fire" and detoxify poison; the fermented black tea (or in China "red" tea- judging from the infuses color, not from the leaves)is rather warm in character, warms stomach, stops diarrhea and helps in the digestion process. The half-fermented (brown) Oolong tea lies in its functions and character between the other two, according to the degree of fermentation.
Therefore it is recommendable to drink green tea for detoxification and cooling inflammations, and black tea for warming the stomach and as to stop loose bowels, Oolong can be a daily beverage and pressed tea is a beverage with sour cream added in Tibet and Yunnan and some small areas, but can increase digestion, fat transformation and reduction.
5. Some notes on tea leaves' characteristics and their preparation
Tea leaves belong to the fragrant herbs and like a warm, dry environment, stored in a tightly sealed box; zinc is the best material for this purpose. Porcelain, earthenware and less good iron (tannic acid corrodes iron) are also possible.
Storing should prevent tea leaves from cold, wet air, contact with fishy, rancid, greasy smells and sharp, alkalic and sour materials. If tea ever has moulded it is not very suitable to drink it anymore; although you can get rid of the mouldy smell by backing the leaves slightly but fragrance, color, astringency are lost (besides the toxins of mould are strong carcerogenics). Although tea is an daily necessarity, but if not be kept in the right way and poured with the wrong method the same tea leaves will have different functions and taste.
The water source for pouring tea is of great importance, since the taste will be unpleasant, if the water source isn't good. it is said already in the Classical tome about tea (Cha Jing): "Water from mountains is superior, from rivers is plain and from wells is inferior." That means water from natural fountains is definitely the best, water from brooks should be boiled to kill micro-organisms and tap water must be stored overnight or undergo longer periods of boiling to make its sediments sink down or oxidize.
The boiling water when ready to pour must first be poured in an instant over the leaves to free them from dust, dirt and cold air in the veins (This is the first pouring which is in China traditionally thrown away).
The fire to heat was one of the objects of the ancient people, who researched the art of taking tea: They distinguished between the warm fire and the vivid fire, meaning coal fire. The latter heated the water over three stages; slowly getting hotter from " tiny bubbles like fish eyes and a light high pitched sound" over "ripples from all sides and strings of pearls (bubbles)" to finally "overturning waves and the whole water in motion". this is called the " boiling method of three stages" which needs vivid (flame) fire to do it. But then again the worst one can do is do let the smoke of the fuel pollute the tea leaves. In the Odd Records of the Qing (Qing yi lu) this is called "Broth of 5 burglars and 6 demons"...
So pouring tea in that way can take a lot of time, nowadays when we drink tea, the most important question is how to benefit our health. We don't need to copy the research of the ancient leisure masters and idle scholars, just use clear, good water, tea leaves that are not moulded, clean teapots and cups and we can any time pour and drink as long as we won't forget to take out the tea leaves in the pot. In this way tea still can be a simple pleasure.
6. The right time to drink tea
Tea can be drunk during the day when thirsty, at work or at leisure. People of ancient times also used tea to rinse their mouths after eating in order to remove greasy residue of the meal without harming the spleen and stomach.
The latter can happen when people drink tea together with or right after the meal; then the tannic acid coagulates the proteins and prevents their absorption. Tea shouldn't be drunk when hungry since it promotes bowel movements, and the widening of the blood vessels increases furthermore the feeling of hunger. It also shouldn't be consumed before going to sleep, since its stimulating coffeine can influence the period of falling asleep and its diuretic alkaline components may urge the sleeper to get up for urination during the night.
7. Side effects of tea consumption
Drinking tea excessively or in huge amounts can be harmful. If a person drinks daily more than one liter of tea, it can lead to a lack of vitamin B1, since the tannic acid reacts chemically with the vitamin and reduces such the amount of available B1.
Forcing oneself to drink more tea than suitable increases the burden of the stomach and leads to incomplete digestion.
Coffeine raises the nightly production of stomach acid, therefore patients with stomach ulcers should also avoid it.
8. Which people are not suitable to drink tea?
1. Patients with high fever who took antipyretic (against fever) since alkali can raise the body temperature and counters the effects of acetylsalicylic acid ( like Aspirinâ ) by a chemical reaction with it.
2. Patients with hypertension, heart diseases, lying-in women, should be careful since coffeine raises the blood pressure in the forebrain, accelerates the heartbeat and reduces the milk secretion functions.
9. Which kinds of medicaments should not be taken with tea?
According to the Herbal Materia Medica (Ben cao gang mu) tea should not be taken together with China root (smilax pseudochina). Of the Chinese herbs all "Bu" (supplementing) medicaments like ginseng, tang-kuei (angelica sinensis) etc. are not suitable for simultaneous consumption since they can lead to a coffeine intoxication by reciprocal interaction.
Among western medicine there is quinine, iron substrates, ephedrine and atropine that should not be taken with tea, since it reduces or influences their effect.
Furthermore tea that has been remaining overnight from the day before or became cold for a long time should not be consumed anymore (oxidation). In Hu Ju's 10 eating taboos (Hu ju shi shi ji) it is said that tea should not be drunk, when one eats Chinese leek (allium tuberosum, jiu), since: "Drinking tea for a long time make light like a feather, but together with leek it makes the body heavy." And finally in the Lost Volumes of the Herbal Materia Medica (Ben cao gang mu shi yi) is recorded: "Patients that suffered from lung diseases have lost blood, their stomach and belly is cold, so they are most unsuitable to drink tea."
1. Drinking tea is good for the digestion, has fat digestion abilities; it is most suitable for obese patients to drink tea (a while) after eating rich, greasy food. A saying from the Sung-Dynasty goes: "One cup of tea in the morning, makes the pharmacist starve from hunger (since he'll run out of business)."
2. Since tea contains traces of fluor, it is recommended to use it often for rinsing the mouth in the evening before going to sleep, such lowering the caries risk. Since they contain tannin, it can make some meat residues between the teeth shrink (by its astringency) and such substitute a toothpick.
3. Although tea has the ability to exite and raise the spirit, but such is not always wished for persons suffering from nervousity or hysteria and insomnia, who take refuge in psychopharmaceutic drugs. In this cases tea might reduce the medicaments' effects and it is better only to drink a cup in the morning and at noon, but not after four o'clock in the afternoon. In this way it takes away the drowsiness resulting from the drug when needed, but doesn't counteract against it when the sleeping time has come.
Even better is to try drinking some strong tea continuously for days and then refrain from drinking it, which (after a natural adjusting) might even make the drug not necessary anymore.
4. Tea is definitely a very good beverage and is beneficial in many regards, but nevertheless the individual case depend on a persons physique and his ways of life as for example if he is used to drink tea, suffers from a weak constitution, hypertension, heart diseases, vacuity and "coldness" of stomach and intestines, and so on; especially if he belongs to this vacuity/coldness group of patients and suffers from a stomach ulcer, then drinking tea is not suitable for him.