Do I need that cup of coffee?
Before I start writing, I need a coffee. Well, I want one, although I may not need it.
We are all very self-righteous when it comes to taking drugs, but every society has its acceptable drugs. Caffeine is ours and it is the most popular drug in the world.
The highest per-capita consumption is in Europe where, despite the popularity of cola and energy drinks, tea and coffee are the predominant sources. More than 90 per cent of the caffeine in Britain is consumed as tea or coffee.
Are the perceived benefits real? I know that as a child, the taste of coffee was abhorrent to me, but I loved the smell of roasting coffee.
Recent tests have shown that caffeine is beneficial for athletic performance. It seems mainly to improve endurance. The doses have been big – equal to several cups of filter coffee, but within the limits set by the International Olympic Committee. It has certainly not been banned – there would probably be an international incident if it were.
When I was student, back in the Middle Ages, we drank coffee to keep awake and took pro-plus pills, which were pure caffeine.
They seemed to work for a while, then you crashed, so it was wise to take them only when examinations were nearly over.
When I bought my first pro-plus, I felt as if I was committing a sin. How innocent we were.
Does caffeine have a beneficial physiological effect or is it psychological – the placebo effect?
Wait a minute, I'll just fill my coffee cup again. I don't want to suffer headaches and fatigue, which are the commonest caffeine withdrawal symptoms.
These can go on for days with heavy caffeine consumers. Flu-like symptoms have been reported. Too much caffeine causes the shakes. After taking a caffeine containing drink, the caffeine is distributed rapidly through the body, reaching its highest concentration in the blood and brain within 30 minutes. For adults, half the caffeine will be eliminated within four to six hours, mainly in the urine. The time is longer during pregnancy and shorter in smokers.
The effects of caffeine seem to depend on whether you are a regular consumer or not. Are you hooked? Morning alertness is not good in caffeine consumers before they have had their first cup of coffee. It seems somewhat like smokers with their first cigarette.
Surprisingly, consumption of caffeine has little or no effect on non-consumers. Also, the level of alertness of consumers does not exceed that of non-consumers. Therefore, we have a physiological, albeit not critical, dependence.
The benefits of caffeine are variously disputed. After a week or so of abstinence, former caffeine consumers come to resemble non-consumers in their waking and daytime level of alertness. This makes a strong case for, if not addiction, then dependence on the part of caffeine users, because they need it to function normally.
Caffeine poses a low risk of true and dangerous addiction, perhaps because the psychoactive effects are not particularly pleasurable.
There is a gene that codes for the adenosine A2A receptor that confers susceptibility to caffeine-induced anxiety – anxiogenic.
Among 6000 people surveyed, only 5 per cent gave the anxiety factor as the reason for giving up tea and/or coffee, so it does not seem to be a major problem.
Caffeine combined with aspirin, paracetamol, ibuprofen and codeine in a variety of available analgesic products shows that caffeine does add to their efficacy, especially in the treatment of headaches. The vasoconstrictive action (narrowing of blood vessels) is likely to be important in this context.
That's fine – fill up my coffee cup please.
- © Fairfax NZ News