Tobacco contains over 4,000 chemicals, some with toxic and irritating effects. More than 40 substances capable of causing cancer have been identified in smoke. These substances are present in both the tobacco leaf itself and arise from the production process and chemical additives in the leaf and glue.

Among all the substances in cigarette smoke, nicotine, carbon monoxide, and tar are the ones that most affect the human body and cause the most diseases.

Nicotine has various immediate effects, including:

Accelerating heart rate; Increasing blood pressure and hormone production; Constricting small blood vessels under the skin; Modifying blood composition and metabolism.

Long-term, the most serious consequence of these nicotine effects is the occurrence of a myocardial infarction (commonly known as a heart attack).

Carbon monoxide is particularly harmful during pregnancy as it reduces the amount of oxygen that should be transported to the uterus and the fetus, leading to abnormalities in the baby’s growth.

Tar consists of a set of carcinogenic compounds and other irritants for the respiratory tract.

70% of the tar from cigarette smoke is deposited in the lungs, giving them a dark appearance.

The irritating substances in cigarette smoke can damage the lungs, causing coughing, bronchiole constriction, and increased mucus production in the airways, leading to chronic bronchitis and pulmonary emphysema.

Furthermore, they damage the small cilia lining the airways, which help clear impurities and bacteria, making the lungs more susceptible to infections.

Many of the substances in tar can cause lung cancer and cancers in other organs.

Smoking is a recognized chronic disease – resulting from nicotine drug addiction – and a risk factor for around 50 diseases, including cancer, COPD, and cardiovascular diseases.

Besides being associated with non-communicable chronic diseases, smoking is also a significant risk factor for developing other conditions such as tuberculosis, respiratory infections, gastrointestinal ulcers, sexual impotence, infertility in women and men, osteoporosis, cataracts, among other diseases.

According to the World Health Organization (WHO), smoking is the leading preventable cause of death worldwide, responsible for 63% of deaths related to non-communicable chronic diseases.

Of these, smoking accounts for 85% of deaths from chronic obstructive pulmonary disease (bronchitis and emphysema), 30% from various types of cancer (lung, mouth, larynx, pharynx, esophagus, pancreas, kidney, bladder, cervix, stomach, and liver), 25% from coronary artery disease (angina and heart attack), and 25% from cerebrovascular diseases (stroke).

The consumption of tobacco and its derivatives kills millions of individuals each year.

Smoking worldwide:

Smoking is considered the leading preventable cause of death worldwide;

WHO estimates 1 billion and 200 million people are smokers;

Men have higher prevalences of smoking than women;

The total deaths due to tobacco use reached 4.9 million annual deaths;

This number is projected to increase to 10 million annual deaths by around the year 2030.

After approximately 8 hours without smoking, carbon monoxide levels in the blood begin to decrease. This brings significant improvements for ex-smokers after their last cigarette:

In 20 minutes:

• Blood pressure returns to the level before the last cigarette, and the temperature of the hands and feet goes back to normal.

In 8 hours:

• Toxic carbon monoxide is no longer present in the blood, and the smoker’s breath starts to fade away.

In 2 days:

• Sense of smell and taste begin to refine.

In 3 days:

• Breathing notably improves.

In 3 months:

• Blood circulation improves, lung capacity increases by about 30%, making walking easier.

In 9 months:

• Fewer infections, respiratory difficulties decrease, and overall performance improves.

In 1 year:

• The risk of cardiovascular diseases is halved compared to smokers.

In 5 years:

• The risk of a stroke diminishes.

In 10 years:

• The risk of lung cancer equals that of a non-smoker.

In 15 years:

• The risk of heart attack and stroke equals that of a non-smoker.

Source: American Cancer Society