It's present in our morning cuppa, our pre-work latte and our afternoon cola, but what are the effects of caffeine and are there any risks in consuming too much?
Caffeine occurs naturally in various species of plant, where it acts as a natural pesticide. Humans consume it in products made from the coffee plant, the tea bush, kola nuts, yerba mate and guarana berries.
What are the effects of caffeine?
- In moderate doses (150-250mg) caffeine counters drowsiness.
- It can increase alertness and help prevent boredom and tiredness interfering with performance on manual and mental tasks.
- Larger doses can sometimes impair performance. There may also be increased levels of anxiety.
- Can increase heart rate and blood pressure and, sometimes, the rate of breathing.
What are the risks associated with caffeine?
- Consuming 500-600mg of caffeine per day (roughly seven cups of instant coffee) is considered excessive, and can have adverse effects.
- It can cause insomnia, muscle tremor, nausea and diarrhoea.
- Caffeine can aggravate high blood pressure and ulcers.
- A psychological dependence may arise in cases of heavy, long-term use.
- Cutting out regular doses of caffeine can lead to users feeling less alert, more drowsy and irritable.
- Death from overdose is possible, but would take about 100 cups of coffee.
- Researchers at the University of Washington found that combining large quantities of caffeine and paracetamol together may increase the risk of liver damage. One to be aware of next time you go for the coffee and pills hangover cure.
- If you are concerned about any of the above, consult your doctor (GP).
Caffeine and the law:
Caffeinated drinks and caffeine pills (such as ProPlus) are sold without restriction.
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