Many people are coffee fans. Coffee has a rich taste, can be refreshing and give you a sense of excitement. However, too much coffee is not good for the brain.
First of all, coffee contains caffeine that restricts blood flow to the brain and other organs. When the brain can not get enough nutrition, brain activity will be reduced.
Coffee makes people refreshing and energetic simply because caffeine can prevent the brain to receive a chemical substance called adenosine. Adenosine will weaken nerve cell activity and make people sleepy. When the brain activity is slowing down, people will fall asleep. The function of sleeping is to supply the chemical substance that the brain needed to help stimulating the nerve effectively. Adenosine will let you know it’s time to sleep and help you to get a deep sleep, which means a good quality sleep.
However, caffeine hinders the function of adenosine and releases the adrenaline, causing mydriasis, faster heartbeat, higher blood pressure, muscle contraction that prepare for response, the liver produces more sugar to the blood to produce more energy…caffeine makes the body stay excited and nervous for a long time, that’s why absorbing too much caffeine will make you hard to fall asleep and also affect the sleeping quality. As a result, when we wake up the next day, we’ll be listless and might want another cup of coffee.
Moreover, coffee causes the brain to produce dopamine that makes people feel good. But when the effect disappeared, people will feel a lot more tired and down; eventually they want another cup of coffee to get back the feeling of excitement and happiness. This effect of coffee is similar to that of amphetamines, though is less serious and not fatal, but if you are addicted to coffee, you’ll be helpless like drug addict. Without coffee, you’ll be so tired, depressed and might get horrible headache.
Therefore, brain expert suggests that we should not drink more than one cup of coffee a day in order to protect our brain.