Dangers and alternatives to coffee drinking habit

Dangers and alternatives to coffee drinking habit

By Jane Clarke

LONDON: Coffee, like tea, is a fine drink, but your body can suffer in numerous ways from caffeine toxicity, if you over- consume - that is, drink more than two to three cups a day. Caffeine, an alkaloid, is found naturally in coffee and tea, but is also added to fizzy drinks, such as cola, some sports/energizing drinks and supplements.

The concentration is highest in coffee, but tea and colas contribution falls only slightly behind. It is impossible to say how much caffeine is present in specific cups of coffee or tea, because it depends on the type used and method of brewing.

A cup of espresso may contain as much as 300 mg of caffeine, while a cup of instant contains only 75 mg. Strangely, filter coffee can contain more caffeine than espresso, because the water remains in contact with the beans for longer. The caffeine content of tea depends principally on the length of time for which it has been brewed, but is likely to be a little less than that of a cup of instant coffee - say 40-50 mg.

However, the average Briton drinks twice as much tea. When it comes to cola drinks, they contain roughly half as much caffeine for the same volume of tea, and a third of instant coffee. Unfortunately, the majority of consumers are children, which means that, because of their size, children receive a similar dose of caffeine from the same quantity of cola as an adult will from coffee. They can be adversely affected by consuming large amounts of caffeine, and while it is not a cause of hyperactivity, children can become restless, irritable and nervous when they consume more than six cans per day, according to psychiatrists from the U.S. National Institute of Mental Health. Numerous children become unsettled by just a couple of cola hits.

Caffeine also inhibits the absorption of both calcium and iron, two essential growth nutrients for children. Likewise, adults who swallow nutritional supplements with their morning coffee or tea are wasting their time: the caffeine can bind the nutrients in the gut and stop absorption. People who have an increased risk of osteoporosis - such as menopausal women or those on steroids on a long-term basis - should make sure their caffeine intake is well within the recommended level, as their bones need all the help they can get to maintain strength. Equally, people who suffer from iron- deficiency anemia should keep caffeine intake down and shouldn't accompany iron-rich meals with caffeine - leave at least two hours or so between eating and having a cup of tea or coffee.

One of the reasons people over-consume caffeine is because of the stimulating effect it has on the brain. This alkaloid goes for brain receptors designed for adenosine, a natural sedative that tells the body to slow down. By overriding and blocking this normal hormonal reaction, caffeine fools the body into staying in top gear. This is fine on the odd occasion, but on a long-term basis relying on caffeine to keep you going undermines the body's natural ability to feel energetic - and to sleep when it needs to. We are mammals that need to sleep and slow down at times; if we're disrupting our resting routines, the body will suffer. To avoid disrupted sleep, don't drink caffeine past mid-afternoon if you can help it. There is, after all, plenty of research - both anecdotal and scientific - to suggest that people who consume caffeine regularly experience lowered mood states, headaches and drowsiness when they stop, which would indicate that caffeine is capable of completely undermining your body's natural state of wellbeing.

The Institute of Food Research has also found that a relationship exists between caffeine-withdrawal symptoms and drink preference. In other words, it's addictive. If you are reducing your caffeine intake, I suggest you do it gradually to avoid the worst withdrawal effects. But once you've got through the initial headaches, low energy and other cold-turkey symptoms, you will feel much more energetic.

Excess caffeine can speed up your heart rate - we all know that fluttering, racing-heart feeling after one espresso too many, or the state of anxiety you sometimes get when you have overdone the tea breaks. For this reason, many cardiologists recommend that people with heart complaints should cut caffeine out altogether.

Excess caffeine can also aggravate premenstrual tension and menopausal symptoms, such as flushes, breast tenderness and fluid retention. And it affects the gut in many ways - some good as well as bad. On the negative side, caffeine can irritate the stomach and esophagus linings, which can in turn aggravate indigestion, hiatus hernias, inflamed ulcers, reflux and other digestive complaints. Further down, caffeine can stimulate the colon and rectum to increase their peristalsis (wave-like movements), which means that if you have a tendency towards diarrhea and malabsorption it can cause you to lose more nutrients.

On the other hand, caffeine may also get a sluggish, constipated bowel going - which is why some people find a coffee hit in the morning helpful.

Of course, drinking decaffeinated coffee or tea is always an option. You should be aware, though, that in many cases the process of decaffeination affects the taste adversely and, more worryingly, involves the use of solvents, such as methylene chloride. Although the beans are subsequently steamed, the process does still leave some residues. Unless the packaging actively states that the contents have only been exposed to water method (not just 'steamed' - it's a misleading term), assume that solvents have been used.

-- Observer News Service