Because tobacco contains nicotine, it is very toxic. It is reported that nicotine in one cigarette can kill 10 mice, nicotine in 25 cigarettes can kill a cow, and 40 ~ 60 mg of nicotine can kill people. Nicotine can damage brain cells and cause central nervous system symptoms in smokers. Lead to high blood pressure, rapid heartbeat, and even arrhythmia and heart disease; Cause stomach diseases such as stomach pain; Damage to bronchial mucosa, causing chronic bronchitis.
More seriously, tobacco will significantly increase the risk of lung cancer, oral cancer, throat cancer, esophageal cancer, pancreatic cancer, bladder cancer and renal pelvis cancer, and may also lead to cancer and leukemia of nasal cavity, sinus, stomach, liver, kidney and cervix. Their risk is determined by the time and quantity of smokers smoking. For some smokers, alcoholic beverages can also aggravate health effects.
However, there is also evidence that smoking does not cause breast cancer and can reduce the incidence of uterine wall cancer.
There is no clear result showing the relationship between smoking and rectal cancer/colon cancer and prostate cancer.
Some objects in the field of smokers, smokers drinking alcohol and smokers being infected by germs will increase the possibility of suffering from certain types of cancer.