Caffeine - what does it really do?
Increased heart rate
High Blood Pressure
And the most serious - convulsions.
Caffeine, as most of us know is a stimulant that is contained in coffee, tea, chocolate, guarana, certain soft drinks, and now in some alcoholic drinks. Stimulants are collectively known as drugs that can increase our energy, arousal, and can create a sense of power and confidence. Out of all the stimulants caffeine is the most commonly taken, and is the mildest of stimulants (as opposed to the amphetamine family, which is one of the most potent of stimulants).
Caffeine in small quantities is relatively harmless e.g. 2 cups of coffee per day. So having a cup mid day from Aramark's office coffee service or Starbucks is still fine, it is when you drink excessive amounts of coffee that it can be detrimental to your health. But there are some people that use it as a source of energy, and may drink up to 10-20 cups of coffee per day. At this level it can produce some very serious problems such as:
In moderation the effects of caffeine are obviously not as severe. In fact to some they would think the side effects of caffeine are beneficial by giving a person the feeling that they are able to concentrate better. This is because caffeine aids with the symptoms of fatigue by suppressing drowsiness, due to its stimulating affects.
But even in moderation e.g. 4-5 cups of coffee (or tea, or soft drinks) can have unwanted side effects. At this level it still affects your blood pressure, and without you knowing, can reduce your memory, resulting in poor concentration. It can also cause irritability. So although your first coffee for the day may pick you up due to the stimulating effects of caffeine, the next few drinks may do the opposite.
Caffeine is a vasoconstrictor. A vasoconstrictor is a substance that causes cells in the brain or body to get smaller, which means less blood gets to the cell (as the cell is smaller). Because blood carries oxygen, there is less oxygen in the cell also.
I have explained this so you can understand how caffeine affects your memory, concentration, blood pressure, and why you can become irritable.
If you have been consuming caffeine in moderate amounts, say 4-6 cups of coffee per day, the cells in your brain are constricting (getting smaller), resulting in less blood, and therefore less oxygen to those cells. Without enough oxygen to the brain, memory and concentration will be affected, as oxygen is essential for your cells to function at an optimal level. So the less oxygen your brain receives, the less efficient it will be at remembering and thus your concentration will be affected (because you can't recall what you were doing). When your brain does not receive adequate amounts of oxygen, you will also become more irritable.
As for your blood pressure, because caffeine can make your cells smaller, there is less room for your blood (which creates more pressure) and therefore your blood pressure will increase. So if you already suffer from high blood pressure, stay away from caffeine, as it will only make it worse.
Another significant problem is that caffeine can cause insomnia. This is because of its stimulating affects. Caffeine can take between 6-12 hours to work through your system, it has been found that as little as two cup of coffee per day (if you are sensitive to it) can affect your sleep patterns. It can also increase your stress levels due to its stimulating effects, so if you suffer from stress, avoid caffeine.
Unfortunately caffeine doesn't really help with the health of your body. It won't really cause any long-term damage if you occasionally have it in small quantities. But for those who use it regularly, watch out, it can harm you.
- Louise Ganey