Caffeine

Caffeine (pronounced ka-feen, kaf-een or kaf-ee-in)

A white, crystalline, bitter alkaloid with the chemical compound C8H10N4O2.

1830: From the French caféine, the construct being café (coffee) + ine (the chemical suffix).  The earlier German was kaffein, from kaffee (coffee); the adjective is caffeinic.  Technically, caffeine is a trimethyl-derivative of xanthine, a coining as Kaffein in 1830, from German Kaffein, by German analytical chemist Friedlieb Ferdinand Runge (1794–1867).  He chose the name because the alkaloid was found in coffee beans; its presence accounting for the stimulating effect of coffee and tea.  The noun caffeinism was coined as medical jargon in 1880 to describe the "morbid state produced by prolonged or excessive exposure to caffeine" although the condition had for centuries been noted by doctors and others.

Of coffee

Caffeine's molecular structure.

Methyltheobromine (or caffeine) is a central nervous system stimulant and the most widely consumed psychoactive drug which works, inter alia, by reversibly blocking the action of adenosine on its receptor and consequently prevents the onset of adenosine-induced drowsiness.  Caffeine is a bitter, white crystalline purine, a methylxanthine alkaloid, chemically related to the adenine and guanine bases of DNA and ribonucleic acid RNA.

Human caffeine consumption is said to date from circa 3000 BC when, according to Chinese legend, the mythological Emperor Shennong (Divine Farmer) serendipitously invented tea, a story derived from an early book on the history of tea.  Coffee drinking first became common in the mid-fifteenth century in the Sufi monasteries of Yemenin Arabia and it spread first to North Africa and by the sixteenth century was widely consumed throughout the Middle East, Persia and Asia Minor.  The first European coffee houses were in Italy and they soon became common throughout the continent.

Voltaire (1760) by Théodore Gardelle (1722–1761); he doubtlessly agreed with de Fontenelle.

In its pure form, caffeine can be fatal in tiny quantities although in the form usually enjoyed, coffee, one would need to drink over a hundred cups in a day to approach toxicity.  Voltaire (1694–1778), often at the Café de Procope in Paris, drank sometimes as many as forty cups a day, enjoying it so much he ignored the advice of his doctors to stop.  He lived to eighty-four but there’s no evidence the often attributed quotation: “It may be poison, but I have been drinking it for sixty-five years, and I am not dead yet” was his.  The more likely source is French author Bernard Le Bovier de Fontenelle (1657–1757) whose actual words were: “I think it must be [a slow poison], for I’ve been drinking it for eighty-five years and am not dead yet.”   Fontenelle died a month short of his hundredth birthday.

Depiction of seventeenth century London coffee house.

Whatever the concern about coffee the drink, the coffee house the place attracted its own concerns.  There’s some evidence coffee houses were welcomed by the authorities when first they became popular in seventeenth century London because they seemed a desirable alternative to the ale house where men would drink beer and later gin, leading to all the notorious social ills.  However, it seemed soon to kings and ministers that while having drunken men brawl or beat their wives was hardly good, it was a more manageable problem than having them cluster, share the newly available cheap newspapers and pamphlets, talk and think.  Men taking and thinking might lead to them getting ideas which was worse than them fighting in the street and government made repeated attempts to suppress the coffee shops.  Ultimately, caffeine prevailed.

Johann Sebastian Bach (circa 1760) by Johann Eberhard Ihle (1727–1814).

On the continent, the Habsburgs were no more impressed than the Stuarts in England, the government there encouraging the idea of coffee was a subversive societal vice and there was something of a minor moral panic among good citizens disturbed at the corrupting influences of such places.  This didn’t amuse a German composer famously associated with the late Baroque, JS Bach (1685–1750) who was fond of taking his frequent shots in his favorite coffee shops and, although never noted for his light-heartedness, he took an amusing poem mocking the public’s concerns, written by his frequent collaborator Christian Friedrich Henrici (1700–1764; pen name Picander), and set it to music as Schweigt stille, plaudert nicht (Be still, stop chattering).  Composed between 1732-1735, it’s usually called the Coffee Cantata, although, it’s really a comic operetta.  A satirical commentary, the work makes fun of the concerns respectable folk had about coffee and coffee houses.  In Vienna as in London, caffeine triumphed.

Despite the joys of a Bach cantata and the persuasive (if misattributed) endorsement of Voltaire, the killjoy editors of the Diagnostic and Statistical Manual of Mental Disorders (DSM) weren’t sure ordinary folk could be trusted to decide how many cups of coffee daily to enjoy and declared more research was needed.  They often conclude more research is needed.  Strangely, the DSM’s editors appear to be less trusting than most clergy, caffeine a drug to which even normally condemnatory priests, rabbis and mullahs don’t object, the only famously abstemious among the major faiths being the Church of Latter-Day Saints (the Mormons), the Seventh-Day Adventists and the Rastafarians, the last perhaps a surprise given how well a long black complements some good weed.

Simple pleasure: the long black.

Widely consumed, caffeine is a psychoactive drug which produces its psychomotor stimulant and reinforcing effects through antagonism at adenosine receptors and indirect effects on dopaminergic neurotransmission.  The editors of DSM-5 (2013) were prepared to concede consumption of caffeine at recommended dietary doses is usually at least harmless and may even have some benefits such as the enhancement of analgesia but do caution some may experience caffeine-related health effects and functional impairment and that this can manifest in different people at different levels of consumption.  Higher doses can produce dysphoric subjective effects and caffeine intoxication, including restlessness, nervousness, insomnia and an irregular heartbeat.  It’s also associated in some with gastrointestinal problems, urinary incontinence and anxiety, use during pregnancy said to be associated with especially poor outcomes.

Lindsay Lohan with coffee, leaving Coffee Bean, Los Angeles, December 2007.

Cold turkey may not be the solution either, the editors documenting withdrawal symptoms which some may experience if abruptly discontinuing regular use, including headaches, fatigue, irritability, a depressed mood, difficulty concentrating, and even flu-like symptoms, the DSM-5 codifying the conditions as (1) caffeine intoxication, (2) caffeine withdrawal, (3) caffeine-induced anxiety disorder and (4), caffeine-induced insomnia.  These are listed as the potential diagnoses when symptoms cause clinically significant distress or impairment and, because some individuals report an inability to reduce their consumption despite clinically significant problems even after seeking treatment, caffeine consumption can be said to lead to substance dependence.

Caffeine is an essential part of the recommended pro ana breakfast.

Thus the DSM-5 proposed three necessary diagnostic criteria for caffeine use disorder: (1) a persistent desire or unsuccessful efforts to reduce or control caffeine use, (2) continued caffeine use despite knowledge of (it’s not specified if an explicit acknowledgment is needed) having a persistent or recurrent physical or psychological problem that is likely to have been caused or exacerbated by caffeine and (3), withdrawal, as manifested by the characteristic withdrawal syndrome for caffeine, or caffeine or a closely related substance being taken to relieve or avoid withdrawal symptoms. Six additional diagnostic criteria included in other substance use disorders, such as craving, tolerance, and taking caffeine in larger amounts or over a longer period of time than intended, were also included as markers for greater severity beyond the three key criteria for caffeine use disorder.  Because caffeine is so widely consumed, to reduce any potential for over-diagnosis, the proposed diagnostic strategy for caffeine, despite sounding onerous, is actually more conservative than for other substances.

Red Bull girls.  One can see the attraction of energy drinks.

The editors did note the paucity of data relating to the prevalence and clinical significance of caffeine use disorder and the suspicion is the interest may have been triggered not the usual suspect, coffee, but the newer generation of energy drinks and diet supplements.  Previous research was apparently too focused on specific, small-subsets rather than the general populations, some of the studies so specialized as to be thought unrepresentative of the general population.  One (very small) study of caffeine use disorder in the United States (reported in the DSM-IV (1994)) found that 30% of caffeine consumers fulfilled the generic DSM-IV criteria for substance dependence as applied to caffeine but this fell to 10% under (the supposedly more realistic) DSM-5 criteria, a hint the concerns of clinical over-diagnosis do need to be taken seriously.  Again, the point was made that more research is required, the extent to which caffeine use disorder is associated with markers of clinical significance such as self-reported caffeine-related distress or impairment, psychological distress, sleep problems, or other drug use is wholly unknown.

The documented study the editors reviewed was the most thorough evaluation yet conducted of the prevalence, clinical significance and correlates of meeting proposed criteria for caffeine use disorder yet it was extensive enough only to inform future research and considerations regarding risk and differential diagnosis, technical points about the parameters of control group populations especially noted.  Despite the apparent lack of robustness, the editors were persuaded the findings did support the inclusion of caffeine use disorder in future editions of the DSM.  Although only a small percentage of sampled caffeine consumers met the proposed key diagnostic criteria, where the standards were met, there were clinically meaningful effects.

All reputable authorities recommend a caffeine intake of not more than 400 mg a day, or two long black coffees.  Many coffee fiends exceed this before breakfast is over.

Caffeine has become more interesting as a drug because of the late twentieth-century phenomenon of the energy drink, the interest not so much in the caffeine content which, can be much more or much less than a cup of coffee but because the pattern of consumption is, in certain sub-groups, so associated with strong alcohol, often on a 1:1 (ie 30-60 ml spirits to 250 ml energy drink) basis, a pattern well known with long-established mixers like Coca-Cola but now in both much greater volume and a much higher caffeine content.  It’s difficult to tell whether a problem has emerged because while the deaths associated with the combination attract attention, the aggregate numbers, impressionistically, seem small and may not be statistically significant.  There's even been the suggestion extreme variations in ambient temperature may have been an at least contributory factor in some deaths.

Caffeine addiction is one of humanity’s most widespread vices and it extends to those driving cars.  In famous tort case, Stella Liebeck v. McDonald's Restaurants, P.T.S., Inc. and McDonald's International, Inc (1994 Extra LEXIS 23 (Bernalillo County, N.M. Dist. Ct. 1994), 1995 WL 360309 (Bernalillo County, N.M. Dist. Ct. 1994), a passenger in a car (a 1989 model with no cup holders) received severe burns from spilled coffee, just purchased from a McDonald’s drive-through.  Although the matter received much publicity on the basis it was absurd to be able to sue for being burned by spilling what was known by all to be “hot” and the case came to be cited as an example of “frivolous” litigation, there were technical reasons why some liability should have been ascribed to McDonalds.  The jury awarded some US$2.6 million in damages although this was, on appeal, reduced to US640,000 and the matter was settled out of court before a further appeal.

Hertella Auto Kaffeemachine, 1959.

In the twenty-first century, some now judge cars on the basis of the count, capacity & convenience of its cup-holders but in the less regulated environment of the FRG (Federal Republic of Germany, the old West Germany, 1949-1990) of 1959, one company anticipated the future trend by offering a dashboard-mounted coffee maker for the Volkswagen Type 1 (better known as “the Beetle”).  The Hertella Auto Kaffeemachine was not a success, presumably because even those not familiar with Sir Isaac Newton's (1642–1727) First Law of Motion (known also as the Law of Inertia: “An object at rest will remain at rest, and an object in motion will continue in motion with the same speed and in the same direction unless acted upon by an unbalanced external force”) could visualise the odd WCS (worst case scenario).

A happy caffeine addict, pouring himself a cup of coffee in his VW Beetle.

That it was in 1959 available in 6v & 12v versions is an indication Hertella may have envisaged a wider market because VW didn’t offer a 12v system as an option until 1963 and the company seems to have given some thought to Newtonian physics, the supplied porcelain cups fitted at the base with a disc of magnetic metal which provided some resistance to movement although the liquid obviously moved as the forces were applied.  The apparatus was mounted with a detachable bracket, permitting the pot to be removed for cleaning.  The quality of the coffee was probably not outstanding because there’s no percolation; the coffee added in a double-layer screen and “brewed” on much the same basis as one would tea-leaves and for those who value quality, a thermos-flask would have been a better choice but there would have been caffeine addicts willing to try the device.  The trouble was there clearly weren’t many of them and even in the FRG of the Wirtschaftswunder (the post war “economic miracle”) the fairly high price would have deterred many although now, one in perfect condition (especially if accompanied by the precious documents or packaging) would command a price well over US$1000.