Coffee is a good partner to learn to work, help to refreshing, but the wrong way to drink coffee will be hazardous to health!

Do not drink coffee when you smoke. Because the coffee inside the caffeine and cigarettes inside the nicotine together will react, it is easy to cause some changes in cells, and induced cancer.
Calcium deficiency can not drink coffee. Each drink a cup of coffee, then we will let the body of calcium damage about 8 mg or so, so the calcium is best not to drink coffee.
 
Can not drink too much coffee. If you drink too much coffee in a short time, you may be poisoned by the excitement of its caffeine.
 
Do not drink coffee at night. Because coffee has a very strong refreshing effect, so if we drink coffee at night when it is easy to cause our symptoms of insomnia, if you want to drink coffee, then the best drink before 4 pm.