Is coffee healthy?
Coffee has always had a tarnished image.
Millions of people around the world drink the most popular beverage of the past centuries every day. At the start of coffee consumption in Europe, coffee (like tea) was seen less as a food and more often as a medicine. Everyone enjoys a cup or two or three or … which makes this substance one of the everyday staple foods.
Scientific studies show that coffee has numerous effects on the human organism. At the same time, numerous rumours and misconceptions about negative effects of coffee consumption on health still circulate among the public and in medical circles.
The historical background
The history reaches back well into the second-to-last millennium. It is wrapped in many legends. One example is that of the goatherd Kaldi, who one night observed how some of his goats – after eating red berries from small shrubs – jumped about cheerfully while the others slept. Kaldi then tasted the berries himself and immediately felt a stimulating effect.
When a monk met him, he noticed Kaldi's euphoric state, made a brew from this plant and realised that his tiredness disappeared and he could stay awake at night and pursue his prayers.
The region of origin is assumed to be the Ethiopian Kaffa. Through slave traders, the invigorating beverage spread across the Arab world and thus became the most traded "commodity" of the time. Via the sea route from Mocha in Yemen, also called Mokka, coffee reached Europe.
The first coffee houses appeared in the Orient and in 1645 in Venice, the important trading city with the Far East. Oxford, London and Paris followed. The matching pastry was served in Vienna in the shape of a Turkish crescent: the first literary mention of the "Gipfeli".
Arabica has a 60 percent share of the world market, Robusta around 30 percent. The economic importance in international trade is undisputed, with an annual world trade volume of 22 billion USD. Every year, 8 million tonnes of coffee are produced in around 90 countries. Brazil is the largest producer with 28% of the world harvest. More than 50 percent is purchased and processed by the USA, Germany, France, Italy and Japan. Every Swiss person enjoys an average of 9.1 kg of coffee per year, which, behind Finland and Norway, is the third-highest consumption worldwide.
Your effect
As early as the 16th century, British doctors described in detail the health benefits of the beverage, ranging from "aids digestion, speeds up thinking, makes the heart light" to "eases coughs, headaches and dropsy". Nevertheless, coffee still has to fight its harmful reputation, which, according to the proven results of numerous studies, is a
stubborn misconception. For some diseases such as liver cirrhosis, diabetes or dementia, coffee even seems to have a clearly protective influence. Because of its invigorating effect and its taste, it aroused people's research drive early on. But only at the suggestion of Johann Wolfgang von Goethe did the German chemist Ferdinand Runge first isolate caffeine in 1820, probably the most important substance in coffee.
Kidney function
Franz Kafka already said: "If coffee really dehydrated the body, I would have long since crumbled to dust". At very high amounts it does stimulate urination, but without, as is commonly assumed, withdrawing water from the body. Thus coffee does not have a dehydrating effect and makes an essential contribution to daily fluid needs.
The cardiovascular system
A very small and short-term increase in blood pressure was only demonstrated in hypertensives. In non-hypertensives, drinking more than three cups of coffee a day shows no difference compared with one cup a day. According to newer studies, coffee is not a risk factor for atrial fibrillation, coronary heart disease and stroke.
Diabetes mellitus
A meta-analysis (a summary of various studies) in 2009 with data from almost 500,000 participants clearly shows an inversely proportional dose-response relationship among coffee drinkers regarding the incidence of type 2 diabetes mellitus. Per cup of coffee consumed, the risk of illness mathematically drops by seven percent. The mechanism of action is not yet known in detail and is part of further studies. A Dutch cohort study with
17,000 participants showed a halved diabetes risk when drinking more than seven cups of coffee daily.
Stomach, intestines, gallbladder
The intestinal muscles are stimulated by the acids and bitter substances in roasted coffee, which have a laxative effect. In a recent study conducted at the Surgical University Clinic Heidelberg, postoperative coffee consumption after large intestine operations produced a bowel-stimulating effect compared with water. An increased risk of developing stomach or duodenal ulcers is also not detectable in various studies, even with high coffee consumption. A US study shows a significantly reduced risk of gallstone formation with at least four cups a day (risk reduction of 45% in men and 28% in women).
Cancer
A recently published meta-analysis of 40 prospective cohort studies concluded that consumption has no harmful effect on health. Rather, protection against carcinomas of the bladder, breast, oral cavity, pharynx, uterus, oesophagus, liver (HCC), leukaemia, prostate and colon/rectum may be possible. We trust that with this information we have brought coffee closer to you and made it wholeheartedly likeable, or cleared up a few misconceptions.
Sources: Coach Magazin, Marcello Corazza and Sascha A. Müller Chirurgische Klinik, Kantonsspital
