It is hard to imagine a life without coffee, tea, or chocolate. The Chinese imbibed tea for its purported medicinal properties, while those of the Arabian Peninsula have enjoyed the aroma and taste of coffee for decades. Chocolate consumption can be traced back to the pre-Columbian cultures of Mesoamerica, three or four millennia ago.

Europe only got its first taste of these substances during the 16th and 17th century, when trade routes began to open between the East and the West. These would prove to change not only the consumption habits of Europe, but also completely obliterate a long-held medical model.

Humourism – a personalised, literal approach to medicine

In medieval times, a much more literal approach to medicine was taken, based on the concept of the ‘four humours’ – four distinct bodily fluids in the human body; namely, black bile, yellow bile, phlegm, and blood. Each individual was thought to have a unique humoral composition, affecting temperament and health.

The four temperaments according to phrenologists.
The four temperaments according to phrenologists.

Illness was thought to arise from an imbalance of humours. Environmental factors, such as diet and activity, affected an individual’s humoural composition. Hence, patients were treated chiefly through diet prescription, with other medical procedures like surgery, being employed only as a last resort.

Each food had its own humoural affliction – hot, cold, dry, or moist – which changed slightly with the method of preparation. For example, a fever, which is associated with ‘too much heat’, would be cured through bloodletting and the consumption of colder foods such as vegetables.

According to translator and historian Mark Grant, Galen, who believed that ‘a good doctor should also be a good cook’ even wrote a piece of work titled ‘On the Power of Foods’, which served as a guide to the humoural afflictions of various foods and included recipes.

Ancient Greek and Roman doctors like Hippocrates and Galen were credited with the development of humoural theory, which became widely adopted by CE 650.

How did these New Age beverages topple humourism?

With the rise in international trade came an expansion in the types of food that Europe was exposed to. The humouristic classification of these novel foods was a matter of great debate. The humoristic natures of coffee, tea and chocolate, especially, were difficult to determine, as they were unlike any other food Europe had ever come across.

New foods imported into Europe such as coffee, tea and chocolate challenged supporters of humoural theory.
New foods imported into Europe such as coffee, tea and chocolate challenged supporters of humoural theory.

“Some people say [chocolate] is fatty, therefore it’s hot and moist,” says Ken Albala, a professor of history at University of the Pacific.

“But other physicians say, if you don’t add sugar, it’s bitter and astringent, so it’s dry and good for phlegmatic disorders. How can something be both dry and moist or hot and cold?”

The same kind of debates occurred with coffee, added Albala, as some doctors thought the drink had a heating effect, while others insisted that coffee cooled the body by drying up certain fluids (an early observation of the diuretic effect in coffee).

Moreover, all three drinks were astringent on their own, but tasted different when mixed with sugar. Hence, debate also centred around which forms were medicinal, and which were not.

The answer depended mainly on how the physician chose to interpret the illness they wanted to cure. Thus, the three ‘misfits’ – coffee, tea and chocolate – cast doubt on the validity of humourism.

The fall of humourism

By the 17th century, new medical discoveries were made which contested the validity of humoral theory. Discoveries such as the body’s circulatory system saw the body being recognised as a well-balanced system, with all parts being essential and working together to ensure optimal function.

However, it was not until the discoveries of the 19th century that the humoural system finally fell, for good.

“Doctors persisted in keeping the Galenic humoural system and resisted people who argued against it,” says Lindemann.

“In mercenary terms, it’s a matter of people preserving their medical monopoly. It’s also probably a matter of conviction.”

The discovery of micro-organisms and rise of new disciplines like pharmacology provided insight into how illness was caused and cured. These could be confirmed due to the invention of more powerful microscopes. As such, the idea of illness arising from humoural imbalance was invalidated.

Although humoural theory is no longer in wide use, its legacy is still evident in aphorisms like “starve a fever, feed a cold” and in certain herbal remedies. The medicinal natures of foods like coffee, tea and chocolate on the body, too, still generate debate in the medical field until today. MIMS

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