It is not good to drink black coffee at night, it is not recommended to drink coffee at night, otherwise it may affect your sleep. The best time to drink coffee is after breakfast, in the morning or after meals, try not to drink coffee on an empty stomach, it is not good for the stomach. The human body produces fatigue is mainly due to the body will produce “adenosine” when it combines with the corresponding receptors will be transmitted to the brain fatigue information, thus producing a sense of fatigue drink and sleepiness. Caffeine in coffee is similar to adenosine in the body, which can replace adenosine and receptors, so that the brain can not receive the message of fatigue to achieve the effect of “refreshing”, so it is not recommended to drink coffee at night. Coffee contains many nutrients beneficial to health, such as potassium, magnesium, iron, zinc, niacin, polyphenols and a variety of amino acids. You can choose the right time to drink black coffee.