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Coffee – rat poison or miracle medicine?


The red berries, or, erroneously, coffee beans of the coffee bush are rich in caffeine and are roasted and used in a rather bitter drink.
Photo: Fredrik Karlsson.
 

Coffee came to Sweden for the first time, somewhere around 1674. Only a small amount arrived, but that was just the beginning. Nowadays people in Sweden consume on average 11 kg coffee per person every year and this is only surpassed by the Finns who consume 12.8 kg.

In 2005 the world production of coffee was 7.7 million tons and Brazil produced more than a quarter of this. There are around seventy different kinds of coffee but the most important beans come from the bush Coffea arabica, which has 70% of the market.

Coffee breaks – an intellectual activity
Coffee houses began to appear in big cities, most significantly London, during the 17th and 18th centuries. They became the meeting places of men with intellectual interests. At that time coffee breaks were an all-male event. Coffee houses were important for spreading news. Politics, literature and science were discussed over a cup of coffee. Many radical thinkers, great philosophers and famous authors made their breakthroughs at these places.

At home Linnaeus considered himself a Turk!
Linnaeus realised that you had to behave like a Frenchman at the Royal Swedish Court, “but when we are at home, we live like Turks: a long and wide dressing gown, loose slippers, a big and white cap, we smoke our tobacco just like Turks; so that the Turks have taught us to dress at home and to drink coffee.”

In general, Linnaeus considered that coffee was good for you and a bracing drink as long as it was taken in moderation and not too near bedtime. However, he also pondered over a French doctor’s declaration in 1715 that coffee shortened a man’s life. In this connection it can be noted that according to a story the King Gustav III should have carried out an experiment on two identical twins who were serving life sentences. He gave one of them three pots of coffee a day and the other tea, in order to see if the drinks affected their lifespan. This is jokingly referred to as the first Swedish clinical trial. Sadly Gustav III did not live to see the final result of his experiment, but the first twin died at the age of 83. The one who drank tea! The authenticity of the story has been questioned.

 
The team leader of Sweden’s first clinical trial never saw the result of his experiment.

Coffee against sleep
Coffee beans contain between 0.8 and 2.5% of the alkaloid caffeine. Studies have shown that coffee awakens one’s thoughts with lively associations and an increased ability to see combinations. The feeling is clearest when you are most tired. These are mainly subjective judgements but similar results have been obtained from more objective measurements. Coffee affects the heart by increasing the heart beat. It has been proved scientifically that it can take longer to go to sleep after having drunk coffee or taken caffeine. In addition it has been shown that the intake stimulates the acidity of the stomach. Nobody has been able to prove that coffee causes stomach ulcers although it can make existing ones worse. The tannic acids that are often found in coffee can be disguised with the help of milk. It is not just the diluting effect that leads to a more pleasant taste, it is also because the proteins in the milk bind the tannin. Both coffee and caffeine are potent diuretics.


Tea leaves contain more caffeine than coffee beans.
Photo: Gunnar Samuelsson.
 

Tea

Tea, in general, is a drink that consists of a hot water infusion of mainly leaves and flowers from various trees and herbs, but it can more specifically be from the leaves of the special tea tree, Camelia sinensis (previously Thea sinensis). Having been harvested, the leaves are dried. When crushed and fermented, enzymes are released that oxidise the tannic substances that occur in the tea leaves which become blackened. The caffeine content of the tea leaf is higher than in coffee beans: between 2.5 and 4.5%. In the actual drink, there is nearly twice the amount of caffeine in coffee as in tea. In addition, tea contains 0.02-0.04% theaflavin and about 0.05% teobromine.


Is black and bitter the main thing?
If you are not looking for the stimulating effects of caffeine, but you do want to drink something bitter and hot during your breaks, then there are local alternatives. Roasted roots of chicory, or serpent garlic, has a history of being a coffee substitute and was not unusual during the Second World War. Acorns and dandelion roots have also been used for similar purposes. In recent years health food stores have begun to sell chicory as a caffeine-free alternative to coffee.

 
The root of chicory, or serpent garlic, was earlier used as surrogate coffee in times of crises.
Photo: Håkan Tunón.