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Caffeine is a drug that is found in tea,
coffee, cocoa, many soft drinks such as colas and some chocolates. It
is also used in a wide variety of medicines especially cold remedies.
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Caffeine
can be manufactured in a laboratory but it mainly comes from the Arabian
coffee shrub, commercial tea plants, cocoa beans and kola nuts. Coffee
is grown in many areas of the world including Africa, Arabia, Central
and South America, Java and Sumatra and the West Indies. Tea is mainly
grown in eastern Asia and South America especially India, China, Indonesia,
Sri Lanka and Japan. Most of the world's cocoa is grown in West Africa. |
On average in the UK,
we drink nearly 123 million cups of tea per day, each cup containing about
40mg of caffeine, but more if the tea is left to brew longer. Coffee is
almost as popular with 90 million cups of coffee consumed a day. About
70 per cent of this is instant coffee containing around 60mg of caffeine
per cup.
HISTORY
Tea and cocoa have been drunk for thousands of years.
Earliest use of tea was probably in China before the 10th century BC. Coffee use is much
more recent and the first record of its cultivation was in Arabia about 675 AD. Tea was
first imported to Europe in about 1600 by the Dutch East India Company and first came to
the UK in about 1660.
Coffee was first introduced to the UK as a medicine but
became very fashionable to drink in the 1670s. Coffee houses sprang up in London. They
attracted literary figures such as Hogarth and Swift, political revolutionaries and
financial entrepreneurs - some of the first banks and the Stock Exchange were started in
coffee houses. Coffee houses caused much controversy. The authorities saw them as
recruiting places for political radicals and women's groups protested that they damaged
family life. The authorities moved to close down all the coffee houses in London. A
compromise was reached where coffee houses could remain open so long as they did not allow
the sale of political books and pamphlets or political speeches.
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houses became less popular and changes in commerce saw coffee consumption fall. England
turned to tea drinking and remains the only country in Europe that consumes more tea than
coffee. In recent years concerns about the effects of caffeine have led to the manufacture
of decaffeinated coffees and teas. |
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Roasted
coffee beans |
THE LAW
There are no legal restrictions on the sale or use of
coffee, tea, cocoa, soft drinks and chocolate confectionery. Certain medicines which
contain caffeine may only be available on a doctor's prescription.
EFFECTS/ RISKS
Caffeine is an 'upper' and helps stimulate
the body, increasing heart rate and blood pressure. It combats tiredness
and drowsiness and makes people feel more alert and able to concentrate.
Many people have a cup of tea or coffee every morning to 'get going'.
However, people also drink tea and coffee to help them relax. Caffeine
also makes people urinate more. High doses can result in people having
headaches and feeling very irritable.
People who drink more than
6 to 8 cups of normal strength tea or coffee a day usually become dependent.
They may find it difficult to stop using and experience withdrawal
symptoms if they try. This can include feeling tired and anxious and suffering
headaches.
"I don't know if I could do without coffee.
That first cup in the morning gets me up. Off to work and the first thing is coffee.
Basically I drink at least 8 cups a day and the stronger the better. If you said to me
don't drink coffee tomorrow I would get very anxious about trying to do it. I don't think
I would last very long without it."
Research into the health effects of long term use of
caffeine is inconclusive. However, some reports have suggested that it can lead to a
higher incidence of asthma, peptic ulcers, kidney, bladder and heart disease and blood
pressure problems.
"We have seen several well-marked cases of
coffee excess.... The sufferer is tremulous, and looses his self-command; he is subject to
fits of agitation and depression; he looses colour and has a haggard appearance. The
appetite falls off, and symptoms of gastric catarrh may be manifested. The heart also
suffers; it palpitates, or it intermits. As with other such agents, a renewed dose of the
poison gives temporary relief, but at the cost of future misery'. Sir T.C. Allbutt and
H.D. Rolleston A system of medicine 1909.
There have also been concerns about the amount of caffeine
consumed by young children particularly in soft drinks and chocolate. Some commentators
have suggested that children who consume a lot of caffeine may become hyperactive. A child
drinking one can of cola will be taking the equivalent caffeine intake as an adult
drinking four cups of coffee.
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