Life's uppers and downers

Buzz

四月 25, 1997

Drawing on the latest findings of neuroscience, Stephen Braun shows that accepted wisdom about what alcohol and caffeine do to us is sometimes wide of the mark. The widespread belief that alcohol is a depressant in high doses and has no genuine stimulant effects is an over-simplification. In fact, it affects the neurotransmitter dopamine in a similar way to the stimulants cocaine and amphetamine. Alcohol also taps into existing stores of endorphins but, unlike opium, morphine and heroin, cannot initiate an intense "endorphin rush". An as yet unknown number of other neurotransmitters including serotonin (the target of Prozac) are affected by "this pharmacological hand grenade".

Braun states that moderate consumption (one or two drinks a day) may be good for the health but is apparently not sufficiently therapeutic for the author to recommend teetotallers to break the habit of a lifetime. Nor does he recommend alcohol as a sleeping draught or as an aphrodisiac: the social lubricant and remover of inhibition turns out to be an inhibitor of natural genital lubrication and other indicators of sexual arousement (largely by dulling the peripheral nervous system). The environmental and genetic influences on alcoholism are explored by the author; both are seen to be relevant factors. Geneticists are in apparent agreement that alcoholism cannot be perceived as the result of a single faulty gene and contemporary research tends to take the approach that such addiction is probably due to the combined influence of several genes. Even with such new insights into how alcohol affects us, many of its workings still remain obscure.

Alcohol, despite its huge popularity with consumers, is easily outstripped by the world's most popular drug - caffeine. Caffeine occurs in over 100 different plant species including, of course, the ubiquitous tea and coffee. The effects of caffeine are of a more simple nature than those of alcohol but, while it is a stimulant, it works in a rather indirect fashion. As Braun puts it, "drinking caffeine is ... like putting a block of wood under one of the brain's primary brake pedals. Caffeine is an indirect stimulant: brain activity speeds up because it can't slow down." By itself, then, caffeine cannot stimulate anything. It can only clear the way for the brain's own stimulants to do their job. Coffee continues to stimulate until the fourth cup of the day. After that, further caffeine intake will either have no effect or will be counter-productive. Again, unlike alcohol, overdosing on caffeine is almost impossible.

The belief that coffee stimulates the creative spirit was undoubtedly fortified by the many historical figures who swore by it - Voltaire, Rousseau, Kant, Balzac and Johann Sebastian Bach (who wrote the "Coffee Cantata" in its honour) among them. On a more general social level the fact that coffee was a stimulant that engendered sobriety and did not impair the consumer's ability to function in the workplace meant that it was perfectly attuned with both the Protestant work ethic and Enlightenment thinking. The human abuse of caffeine, while unable to realise itself in intemperance, nevertheless manifests itself in its role as a performance enhancer in athletic competition. Many athletes are aware of its potential and the author notes that it is especially popular with professional cyclists, some of whom insert caffeine suppositories before a race. Caffeine's reputation as a suppressor of appetite and even as a direct agent in weight loss are claims that are now largely rejected by scientific researchers. As a result of such findings, in 1991 the US Food and Drug Administration banned caffeine from all diet pills and allied products. For Braun, the "deep dichotomy between reason and irrationality can be seen in the world's tremendous appetite for alcohol and caffeine. Alcohol is the liberator of the irrational. Caffeine is the stimulator of the rational. It would appear that the human spirit craves both poles and turns to these most familiar of drugs to achieve those ends." His final chapter on the use of the two substances together is thus a survey of the individual's attempt to alter, by chemically tipping the balance towards either rationality or irrationality. It is only in the rare moments of complete drunkenness or total sobriety that either pole is ever attained. The rhythm of daily life consists mainly of subtle and perpetual mood swings between the distant poles. That the average adult usually has at least one of these drugs in his or her body at any given time means that our sense of the rational and the irrational is permanently overlaid by the chemical dialogue of these culturally charged substances.

Richard Rudgley is the author of The Alchemy of Culture: Intoxicants and Society.

Buzz: The Science and Lore of Alcohol and Caffeine

Author - Stephen Braun
ISBN - 0 19 509289 9
Publisher - Oxford University Press
Price - £17.99
Pages - 224

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