A description of the way the intake of caffeine affects the brain processes, causing alertness and pleasure.

Every morning many of us wake up with the thought: “I need a coffee”. Why do we feel like this and is it a good thing or not?

Coffee, tea, chocolate and other food and drink have an effect on us because they contain the chemical Caffeine. The more systematic name for Caffeine is 1,3,7-trimethylxanthine and it is found naturally in coffee beans, tea leaves and cocoa nuts. Caffeine is an addictive drug, it enhances awareness, keeps us awake, our heart rate increases and our muscles tense up. It generally gives us a good feeling and is useful if we are tired and have an important task to undertake. Why does this happen?

When caffeine is consumed by the body, two of the body’s chemicals are affected. One is called Adenosine. This is a chemical in the brain that is produced when the body gets tired. Adenosine binds to certain sites (receptors) in the brain which has the effect of slowing down nerve cell activity, bringing on drowsiness. It also makes the blood vessels in the brain dilate (increase in size) so that more oxygen will get to the brain while the body sleeps.

Caffeine has a similar structure to adenosine so it binds to the receptors in its place and blocks those sites. This means that the nerve cell activity actually speeds up, making the person more alert. It also causes the body to release adrenaline, thinking that there is an emergency. This dilates the pupils, opens up breathing tubes, and blood is diverted from the stomach to the muscles, preparing for fight or flight.

The other chemical affected by caffeine is Dopamine. This is a chemical that activates the pleasure centre of the brain. Caffeine causes the brain to produce dopamine in exactly the same way as amphetamines. Heroine and cocaine manipulate the dopamine levels in the brain by a different method. This is why caffeine makes you feel good.

Drawbacks

Caffeine affects the body’s ability to rest and sleep. In the long term this leads to fatigue and anxiety. If a person stops consuming caffeine, this will lead to increased tiredness and depression, because the body has been used to the higher levels of adrenaline. Also headaches are caused because the blood vessels in the brain dilate more than they should without the constricting influence of caffeine.

Caffeine is a drug. It is similar to the controlled drugs, just milder in its effects. Caffeine is found in high levels in coffee and tea. It is also added to many soft drinks. Chocolate also contains caffeine in quite high quantities. Many people across the world consume caffeine regularly every day because they are addicted, they need to drink a cup of coffee or tea or eat a chocolate bar.

We need to be aware of these facts so that we can decide whether to continue to partake of this drug or try to kick the caffeine habit.

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