Author: Dr Ranjeet Singh
Tea is one of the most widely consumed drinks. It is taken mainly as a drink for its stimulating effect. It helps to get over a tired feeling and one feels refreshed after drinking it. This repetition leads to tea drinking habit which in course of time becomes so deep-rooted that it is difficult to give it up after some time. The most active alkaloid principle in tea is caffeine. This is addictive drug similar to cocaine in as much as it stimulate the central nervous system. These effects are short-lived but it has been observed that they lead to withdrawal symptoms of irritability, lethargy, headaches, anxiety and insomnia. This show that it is quite a strong drug to constitute a potential health hazard.
The wide- spread consumption of tea is a striking example of the manner in man for a profit. It is believed that almost a billion cups of per day are consumed all over the world. In India, even slogans like “Roz Chai Peo, Bhut Din Jiyo” ( drink tea daily and live longer) were invented by the vested interest to mislead common people to believe that tea gives strength and vitality.
Tea is prepared from the leaves of an evergreen shrub belonging to Camellia family. The plant is native of South East Asia. In ancient times, the leaves were probably eaten or boiled into a beverage. The earliest record of its cultivation comes from China in the 4th century A.D. By 8th Century, is was quite popular in China and established in Japan. Over the next 600 years or so, the method of infusing tea in water slowly evolved.
Composition of tea?
To ascertain the effect of tea on health, it is essential to know the chemical composition of tea leaves. On an average they contain-
- Moisture = 5-8 %
- Aromatic oil = 0.5 %
- Caffeine = 2.5- 5 %
- Nitrogen = 4.75- 14 %
- Minerals = 5-5.75%
( Source: Nature Cure- BM BHAKHRU)
Harmful Effects of Drinking Excessive Tea?
The harmful effects of tea in case of certain specific diseases are discussed below:
Tea is said to slow down digestion. Its daily intake causes indigestion as it impedes the action of ‘ptyalin‘ a digestive fragment of saliva which acts on cooked starch. The inhibition of saliva seems to be due to tannin. This effect disappear if milk is added to it, as the protein of milk precipitates the tannin. Tea is also said to delay stomach digestion. It can lead to gas formation, diarrhoea, and constipation.
A define effect of caffeine is diuresis. Experiments show that caffeine in 5 cups of tea increases the urine by 400- 500%. This continued stimulation of kidneys by caffeine may damage them. Tea my also promote kidney stones because of high content of oxalate.
Drinking tea can aggravate the symptoms of premenstrual syndrome. This was discovered by Dr Annette Rossignol and associate professor of public health at Oregon State University. He noted that women in China who drank one half to four cups of tea a day were twice as likely to have PMS as non drinkers. Drinking 8 cups a day increased their PMS incidents about tenfold.
Drinking excess tea lead to into incontinence or frequent and urgent impulse to urinate. In a study conducted at St. George Hospital in London, it was discovered that caffeine can exert pressure on the bladder by causing the muscles surrounding it to contract, increasing the need to urinate in some incontinent individual.
The respiratory and cardiac centres are also stimulated by caffeine as coronary arteries get dilated resulting in an increase in the rate of blood flow. It is also said to increase blood sugar level. The quickning of respiration lowers the level of carbonoxicide and increase the heat production of the body by 10-20 %.
It is thus clear that tea, if taken in excess, causes indigestion, over excitability of the nervous system, irritability, palpitation and sometimes prostration. To minimize the harmful effects of tea, it should be induced by pouring boiling water over the leaves and will be allowed to draw for about four to five minutes, then the liquid should be poured into another pot. Mint and Lemon grass should be added. This will help in relieving stomach disorders like flatulence and supply vitamins.