The harm of drinking too much coffee comes first from the caffeine contained in it, because caffeine excites the nerves, stimulates blood vessels, accelerates the heartbeat, and excessive consumption of coffee can cause sinus tachycardia and ventricular tachycardia, increased blood pressure, and insomnia at night. So don't drink too much coffee.

Six kinds of people should not drink coffee:

Suffering from hypertension, coronary heart disease, atherosclerosis and other diseases - long-term or large amounts of coffee consumption, can cause cardiovascular disease.

Elderly women - coffee will reduce calcium, cause osteoporosis. After menopause, women need to add ten times the amount of calcium per day.

Stomach disease patients - drinking too much coffee can cause worsening of stomach disease.

Pregnant women - drinking too much coffee can lead to fetal malformation or miscarriage.

Vitamin B1 deficient people - Vitamin B1 can maintain the balance and stability of the nervous system, and coffee has a destructive effect on it.

Cancer patients - Drinking too much coffee has a carcinogenic risk for normal people.