Wherever I go nowadays I am assailed by do-gooder health nuts.

For example: going out to lunch used to be a real treat ? now you have to make it through an hour without a cigarette (unless there is a verandah at the restaurant, and even then you feel guilty having a puff); you have to water down the wine or follow the example of your healthy lunch-date who is drinking spring water only; you have to dine on lettuce leaves instead of hamburgers and chips, unless you want the waitress and rest of the clientele to stare meaningfully at your fat rolls; and ? worst of all ? to be ?in? and healthily trendy, you have to order decaffeinated coffee at the end of the meal to set you up for a hectic afternoon.

So far I have managed to conform to all the rules ? in public anyway ? for a fashionable healthy lifestyle, all except for one: no way will I succumb to ?decaff?, no matter that full-blown real coffee may give me nightmares, keep me awake, give me heart palpitations, raise my blood pressure, constrict the blood vessels in my brain, etc. etc. etc.

When a long-term friend started a rather heated argument with me on the subject recently, however, and told me that I am a caffeine addict who might as well be taking heroin several times a day instead of those ?poisonous? cups of coffee, I decided to investigate. What are we coffee-junkies doing to our bodies? Why and how does caffeine give us such a buzz?

Firstly, dear friends, let me assure you that by avoiding coffee in your diet, you are not necessarily avoiding caffeine! If you eat chocolate, drink cocoa or tea, consume cola (even diet cola), enjoy those ?energy drinks? at parties, or take certain pain relievers or diet pills, you are taking in large amounts of caffeine.

Caffeine is known medically as trimethylxanthine (you would probably need a big slug of coffee before you could attempt to pronouce that one!). Its stimulant properties have been known since around the sixth century AD, after the coffee plant was discovered by Arabs and its berries used as food and medicine. First they made a kind of wine with the berries (coffee wine ? are there marketing possibilities there?), or dried the berries, crushed them and mixed them with fat to be eaten.

A few centuries later a bright monk roasted some coffee beans and tried making a drink out them ? voila, the first cup of coffee, that made sure everyone stayed awake at prayers. (This information comes from a very enlightening book called Caffeine Blues by Stephen Cherniske).

Latterly we have discovered that caffeine is contained in tea leaves, kola nuts and cocoa beans as well, so we have plenty of sources for this stimulating substance, which can now be isolated in its pure form (a white crystalline powder with a bitter taste).

Modern medics regard caffeine as an addictive drug (I can verify that claim!) ? according to one source it ?operates using the same mechanisms that amphetamines, cocaine and heroin use to stimulate the brain?.

So many bad things have been attributed to caffeine (most notably increasing risk of heart disease, raising blood pressure and anxiety levels, as well as causing sleep disturbances) that it is easy to overlook the fact that it is often used medically as a cardiac stimulant and a mild diuretic ? I have also read about a study that is looking at the possibility of coffee-drinkers being less at risk of developing Parkinson?s disease.

Like most of those natural gifts that we have discovered, it is not caffeine that is bad, but how much we use and for what purpose, it seems.

How much caffeine is bad? An online article from Healthy Eating Club.com suggests one does not take in more than 200 milligrams of caffeine per day. A ?large amount? is considered to be anything over 350 mgs per day ? consume this much and you could experience ?chronic insomnia, anxiety, depression, heart palpitations, stomach upset and ulcer?.

These amounts translate to saying that about three cups of coffee a day ?will not do any harm? and ?may indeed provide some health benefits?. This, of course, does not take into account any other sources of caffeine ? like soft drinks ? that you might consume during a day as well.

  • Click here for a useful table showing the caffeine content of various common drinks, beverages, foods and medications, so you can get an idea of how much you are consuming.

    Note that ?drip? and percolated coffee will give you a far bigger caffeine ?hit? than instant, and black tea will give you almost double the dose you get from green tea. The caffeine content of various makes of cola differs quite remarkably, too, as do those of other well-known soda brands.

    What can happen to you if you ?overdose? on caffeine? According to Howstuffworks.com:
    Overdoses can have effects as simple as the shakes or restlessness, but the effects can go much deeper. A 250mg dose in a very short period can also cause nausea, headaches, tense muscles, sleep disturbances and irregular heartbeats. Over 750mg can cause delirium, light flashes and ringing ears. Finally, extreme doses (about 10 grams for an average-size person) are fatal.

    So, caffeine can be a killer ? fortunately though this would take 100 shots of espresso in a fairly short period of time, and even I ? a confirmed addict ? would find that difficult to swallow! Watch out for those caffeine-rich ?energy drinks? recommended to make you fly high, however ? they are not designed for ?down-downs? when you next play party drinking games. (By the way, most of the well-known brands of those energy drinks contain similar amounts of caffeine per can to a cup of brewed coffee.)

    Now I know the full story I plan to keep chugging the capuccino ? no more than three cups a day, though, I promise!

    What did you think about this article? Send your response to the Highlife Editor.