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Harmful Effects of Smoking

Many teenagers and adults consider smoking fashionable and enjoyable. Many think of it as a way to release stress. Some are addicted to smoking. However, when a person smokes, a lot of harmful substances get into the body.

Tobacco is a product from the leaves of the tobacco plant. It is dried and then used to make cigarettes.

There are more than 4,000 substances in cigarettes. Some of these substances are harmful. They can cause heart disease and lung cancer. Smokers may also suffer from bronchitis. A person suffering from bronchitis will cough badly and often have difficulty breathing.

Harmful substances in cigarettes

The effects of smoking on health are serious and even fatal. This is due to the many harmful substances found in tobacco. The most harmful substances found in cigarette smoke are tar, nicotine, carbon monoxide and irritants.


Tar is a brown, sticky substance that builds up in the lungs during smoking. Tar causes the following harmful effects:

  • Damages the cilia in the throat
  • Damages the cells in the lungs – this decreases oxygen supply to the bloodstream, and
  • Causes lung cancer


Found in Tobacco, Nicotine is an addictive substance. This gives the smoker the urge to smoke more. It causes harmful effects such as:

  • Blood clotting
  • Increased blood pressure
  • Headaches, and
  • Damage to the heart and blood vessels

Carbon monoxide gas

Carbon monoxide gas is a poisonous gas. It reduces the capacity of blood to take in oxygen from the lungs.


Cigarette smoke contains substances that irritate the cells in the lungs. This causes smokers to cough. Prolonged smoking habits can lead to a lung disease called emphysema. This disease damages the lungs and makes the smokers feel breathless. Irritants can also cause cancer.

Harmful effects of active and passive smoking

Did you know that cigarettes do not just harm smokers? When someone smokes near you, you breathe in the harmful substances. This is called passive smoking.

Passive smoking by pregnant women can affect the mental and physical development of the fetus. This may lead to a miscarriage or a stillborn child.

There are many diseases caused by active and passive smoking.


Studies have shown that the more you smoke, the greater the risk of getting lung cancer.

Chronic bronchitis

In chronic bronchitis, the cells in the main air passages to the lungs become inflamed. Excessive mucus is secreted. This reduces the airflow in the air passages, making breathing difficult. The person coughs and wheezes persistently to clear the air passage. This makes the lungs more likely to be infected by bacteria.


Emphysema is commonly associated with chronic bronchitis and smoking. The intense coughing causes the air spaces to enlarge and decreases the surface area of the lungs. This reduces the absorption of oxygen. An affected person spends a lot of energy just to keep breathing and can suffer breathlessness during exertion.

Cigarette packs often have warning on the consequences of smoking printed on them.

Ways to refrain from smoking

Here are some ways to help people stop smoking.

  • Educate them on the harmful effects of smoking.
  • Place health warnings on cigarette packets.
  • Stop people from smoking in public places such as restaurants, offices, lifts and on public transport.
  • Display ‘no smoking’ signs in public places to discourage people from smoking.
  • Stop tobacco companies from advertising, especially in magazines and over television.
  • Educate your family members and friends on the dangers of smoking.
  • Get involved in healthy activities such as sports and community service.


Vaping is the inhalation of an aerosol made by an electronic cigarette (e-cigarette). It is common among the young generation. E-cigarettes (often called vape pens) are operated by battery and heat a liquid until it is turned into an aerosol, which is then inhaled. This aerosol usually contains nicotine; some even contain marijuana.

Just like normal cigarettes, e-cigarettes pose grave health risks. They are highly addictive. It causes anxiety and depression. Long-term use has been found to cause memory loss, loss of concentration and self-control and attention deficit especially in the developing age. Just like normal cigarette smoking, vaping also causes chronic bronchitis. Sleep problems, sexual dysfunction and lasting damage to the lungs are also other side-effects.

Since vaping usually starts at teenage, school-going children must be educated about the negative effects of vaping.