Tobacco contains a number of poisonous in it. The two most important are the tar and an alkaloid nicotine. Nicotine is a strong stimulant as well as a poison. It is second only to cyanides in its destructive effect on the human body. Tobacco is inhaled through beedi, cigarette or hooka or is chewed as such. In moderate does, it tends to stimulate the higher centre of the brain and has soothing effect but in large amounts, it has sedative effect.
Continuous use of tobacco makes a person addicted to it. Some of the adverse effects of tobacco on the human health are given below:
1. Tobacco use causes cancer of lungs, mouth, larynx and oesophagus. Cigarette smoking is the main cause of lung cancer. Tobacco chewing is a proven cause of the mouth.
2. Heavy smokers suffer from bronchitis and shortness of breath (emphysema, a chronic ling disease). Tar present in smoke of tobacco deposits in the nose, throat and lungs causing cough and irritation.
3. Nicotine present in tobacco may cause premature hardening of arteries leading to rise of blood pressure and heart attacks.
4. Beedi and cigarette smoke may contain carbon monoxide, hydrogen cyanide and unoxidised nicotine. All these substances are highly injurious to health.
5. Smoking during pregnancy is associated with miscarriages. Premature delivery and small babies.
6. Tobacco smoke also contains pyridine which causes darkened teeth.
7. Smoking also harms digestion.
8. Hooka is comparatively less harmful way of smoking tobacco as smoke passing through water loses some of its harmful ingredients. Since tobacco, smoking temporarily increases blood pressure and puts a strain.