High caffeine coffee refers to coffee with high caffeine content, but there is no clear standard. Generally speaking, high caffeine coffee is only higher than ordinary instant black coffee. Different people have different tolerance to caffeine and feel different refreshing effects.
Drinking black coffee in moderation can refresh the mind, enhance thinking ability, restore muscle fatigue, raise heart rate, raise blood pressure and relax smooth muscle. But taking caffeine in large doses or for a long time may cause harm to human body, especially addiction. Once you stop using it, you will have various withdrawal symptoms such as mental fatigue, lethargy and weakness.
In addition, coffee has a remarkable refreshing effect and should not be drunk before going to bed. Patients with chronic diseases such as hypertension and hyperlipidemia are not suitable for drinking.