The king Gustav III viewed coffee consumption as a threat to the public health and was determined to prove its negative effects. It is said that he decided to carry out an experiment on two prisoners. Two twins had been tried for the crimes they had committed and condemned to death. Their sentences were commuted to life imprisonment on the condition that one of the twins drank three pots of coffee every day while the other drank the same amount of tea, and this for the rest of their lives, in order to see if the coffee affected their life expectancy. Unfortunately the king died before the final result of his experiment: the first twin died at the age of 83 and he was the one who drank tea!
Barstow Desert Dispatch - Jan 7, 1991
Wikipedia notes that the authenticity of the coffee experiment story has been questioned. Though it doesn't say why.
As far as I can tell, the earliest English-language reference to the story appeared in a 1937 issue of The Science News-Letter. This account was then widely reprinted in newspapers (see below).
The Science News-Letter attributed the information to the Swedish-born botanist Bror Eric Dahlgren, who was a curator at the Field Museum in Chicago. Dahlgren did author a 1938 pamphlet about the history of coffee, which you can read online at the Biodiversity Heritage Library, but it doesn't include the story of King Gustav. I can't locate where else Dahlgren might have told the story of the coffee experiment, which makes it impossible to check his references.
A 44-year-old man presented in May, 2001, with muscle cramps. He had no medical history of note, but volunteered the fact that he had been drinking up to 4 L of black tea per day over the past 25 years. His preferred brand was GoldTeefix (Tekanne, Salzburg, Austria). Since this type of tea had given him occasional gastric pain, he changed to Earl Grey (Twinings & Company, London, UK), which he thought would be less harmful to his stomach. 1 week after the change, he noticed repeated muscle cramps for some seconds in his right foot. The longer he drank Earl Grey tea, the more intense the muscle cramps became.
After 3 weeks, they also occurred in the left foot. After 5 weeks, muscle cramps had spread towards the hands and the right calf. Occasionally, he observed fasciculations of the right adductor pollicis and gastrocnemius. Additionally, he noted distal paraesthesias in all limbs, and a feeling of pressure in his eyes, associated with blurred vision, particularly in darkness...
The patient assumed that there was a relation between his symptoms and his tea consumption, and stopped drinking Earl Grey after 5 months, reverting to pure black tea again. Within 1 week, his symptoms had completely disappeared. Symptoms also remained absent if he completely withdrew from tea, which he did in the nature of experiment, for about a week. He found that his symptoms did not recur as long as he consumed no more than 1 L of Earl Grey daily.
When last seen in November, 2001, neurological examination, nerve conduction studies, and electromyography were normal. He was still drinking 2 L of plain black tea daily (his entire fluid intake), and had no complaints.
The moral of his story is that 2 liters of tea a day is apparently fine. But 4 liters is asking for trouble.
The French scholar Arsene Thiebaud de Berneaud liked his coffee black. So much so that he "opposed with ferocity the then comparatively new custom of adding milk or cream to black coffee."
"He seems to have had an obsession that all mixtures of fluids were injurious... Sustained by this preconceived notion, he was able to publish a long diatribe in 1826, in which he accuses cafe au lait of causing almost every derangement known to medicine."
I've been able to find almost no other information about de Berneaud, so this one odd theory seems to be the most enduring thing he left behind.
Nordic entrepreneur Jakutyte is trying to launch a new product on Kickstarter. It's coffee for dogs. Or, as she's calling it, "Rooffee." She came up with that name, she said, by combining the words roots and coffee. (Surprised me it wasn't Wroof and coffee... but that would be Wrooffee.) She swears she didn't know there's a date-rape drug called roofies. She's posted an update on her Kickstarter page saying she's gonna change the name... but hasn't decided to what yet.
Her coffee for dogs doesn't actually contain any coffee. She says it's "a coffee type of drink made from Nordic wild roots containing no agricultural chemicals or pesticides, no caffeine, and no other nonsense." So it's actually brown liquid for dogs.
Paul Di Filippo
Paul has been paid to put weird ideas into fictional form for over thirty years, in his career as a noted science fiction writer. He has recently begun blogging on many curious topics with three fellow writers at The Inferior 4+1.