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Caffeine and its effects

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Coffee-lovers, take note. That daily cup of java you consume in the mornings is considered a drug. A naturally occurring compound found - in varying quantities - in over 60 plants, caffeine is a stimulant that affects the central nervous system. However, while it can cause addiction or even fatal overdoses in some severe cases, caffeine has little to no negative impact when taken in moderate amounts.

Caffeine sensitivity

Different people have varying reactions to caffeine, and this is often due to an individual’s physical size and frequency of consumption. Taking in large amounts on a regular basis would cause someone to become less sensitive to caffeine over time; such people would usually need a greater dosage in order to benefit from its effects. On the other hand, someone less accustomed to drinking caffeinated beverages might suffer from some discomfort upon ingesting, say, a cup of strong coffee. Some common symptoms include restlessness and increased heart rates.

Positive effects of caffeine

Upon ingesting caffeine, your body will begin to experience its effects very quickly, and these take about six hours to wear off. As most would already know, caffeine helps to raise levels of alertness, allowing an individual to concentrate better on their tasks at hand. A cup of coffee can certainly perk you up sufficiently following a wakeful night in bed.

In addition, some studies have also discovered a link between caffeine and improved memory, viewing it as a potential defence against brain cell destruction. Scientists have, in recent years, been looking to use caffeine in the treatment of diseases such as Alzheimer’s and Parkinson’s.

Addiction, withdrawal symptoms and overdosing

As with all drugs, caffeine is an addictive substance, and users who constantly rely on caffeine to keep alert will find themselves unable to function normally without their daily brew. The withdrawal symptoms are, namely, headaches, tiredness, grumpiness, muscle aches, and even depression in more severe cases.

It is a proven fact that caffeine can kill. Indeed, there have been several fatal cases of people overdosing on caffeine. While these are rare, too much caffeine can indeed cause negative side effects, including restlessness, anxiety, rapid heartbeat, nausea, lightheadedness, vomiting, and cardiac arrhythmia.
Although sensitivity to caffeine varies from person to person, as explained earlier, the typical adult with no pre-existing medical conditions can safely ingest up to around 300 milligrammes in one day. Younger individuals and those with heart-related illnesses should take smaller amounts.

For a clearer idea on the quantities of caffeine present in your daily energy-boosters, have a look at the following table:


Amount of caffeine

A single shot of espresso

77 milligrammes

A cup of brewed coffee

163 milligrammes

A cup of black tea

42 milligrammes

A cup of oolong tea

37 milligrammes

A can of Coke

34 milligrammes

A can of Red Bull

80 milligrammes

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