Not good.

As the big test approaches, it's best for teens who never drink coffee to avoid trying it. For those who are already dependent on coffee, it's not advisable to stop drinking it right away. Experts suggest that you can gradually reduce the frequency and amount of coffee, and gradually replace it with light green tea. It is worth noting that it is not recommended to drink coffee on the day of the exam, because the diuretic effect of coffee is likely to be detrimental to the candidate's ability to answer questions for a long period of time

The caffeine present in coffee and functional beverages is indeed excitatory to the brain, but the magnitude of its excitatory effect varies from person to person. If teenagers drink coffee occasionally and in small quantities, it can have a refreshing effect for a certain period of time and will not cause major damage to the body. However, it is important to note that if you never drink coffee before, and you want to drink coffee to refresh yourself before a big test, you must pay attention to the amount of intake, to avoid excessive excitement and disrupt the normal biological clock, affecting sleep or causing discomfort.

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Additionally, the consumption of large quantities of coffee may cause adverse effects on the growth of the body. The actual fact is that the actual caffeine is actually the most important thing that you can do. A large amount of caffeine over a long period of time can produce a series of adverse reactions, such as nervousness, irritability, anxiety, muscle twitching, insomnia and heart palpitations, etc. In addition, because of the caffeine's ability to make you feel better, it can make you feel better. In addition, because caffeine can increase stomach acid, sustained intake of high doses can lead to peptic ulcer, erosive esophagitis and gastroesophageal reflux disease. People with stomach problems are advised not to drink coffee.

People's Daily News - Exam day should be careful to drink coffee refreshing? Beware of the impact on sleep