Smoking

Smoking is a chronic and addictive disease that causes nicotine dependence. It is a condition directly associated with a significant increase in the risk of cardiovascular, respiratory, and oncological diseases, among others. The World Health Organization (WHO) estimates that 7 million deaths occur each year as a direct consequence of tobacco consumption.

A person is considered addicted to tobacco when they smoke at least one cigarette per day. Contrary to common belief, pipe and cigar smokers (even if they do not inhale the smoke) are exposed to the same or even greater risks than cigarette smokers due to the higher nicotine content.

The harmful effects of tobacco on the body affect not only active smokers but also passive smokers—those exposed to tobacco smoke. Additionally, smoking during pregnancy causes harm to the baby.

Tobacco contains approximately 7,000 chemical substances that damage the body and increase predisposition to cancer. The most notable components and their effects on the body are:

• Nicotine: produces addiction and has a stimulant effect responsible for increased heart rate, nervousness, and irritability.
• Tar: inhaled with smoke, promotes the formation of cancerous tumors.
• Carbon monoxide (CO): produced during tobacco combustion. It enters the pulmonary alveoli, transfers to the blood, and is distributed throughout the body. When hemoglobin carries CO, its capacity to transport oxygen to tissues is reduced.

Smoking is considered the leading preventable cause of disease and premature death worldwide, surpassing illegal drug use or traffic accidents.

Symptoms

Individuals addicted to tobacco present the following characteristics:

• Inability to quit smoking. Most patients have attempted to quit multiple times without success.
• Evident signs of withdrawal when trying to quit.
• Smoking within the first 30 minutes after waking.
• Continuing the habit despite health problems related to smoking.
• Avoiding activities or places where smoking is prohibited.

The main physiological symptoms of tobacco use are:

• Loss of appetite.
• Decreased sense of smell and taste.
• Temporary improvement in mood.
• Increased production of saliva and phlegm.
• Persistent cough.
• Throat irritation.
• Shortness of breath.
• Chest tightness.
• Wheezing: breathing sounds.
• Increased heart rate by 10–20 beats per minute.
• Elevated blood pressure by 5–10 mmHg.
• Excessive sweating.
• Diarrhea.
• Nausea.
• Hypoxia: reduced tissue oxygenation, leading to:
• Fatigue.
• Dizziness.
• Loss of agility.
• Lack of concentration.
• Nicotine dependence to perform daily tasks.

Withdrawal signs appear 2–3 hours after the last cigarette and typically intensify during the first two to three days of quitting. The most common are:

• Intense craving for tobacco.
• Sleep disturbances: drowsiness or insomnia.
• Nightmares.
• Anxiety.
• Restlessness.
• Tension.
• Depression.
• Increased appetite.
• Weight gain.
• Difficulty concentrating.

Causes

Smoking is caused by nicotine, which rapidly reaches the brain and stimulates dopamine production, generating a pleasurable sensation that improves mood. Nicotine is addictive, so the more a person smokes, the more they require to feel well.

Smoking behavior is often associated with routines that prompt tobacco consumption at various times of the day, such as drinking coffee or alcohol or during rest periods.

Risk Factors

The primary risk factor for smoking is the act of smoking itself; even one cigarette can lead to dependence. Additional contributing factors include:

• Age: starting smoking during adolescence.
• Genetic predisposition.
• Parental or peer smoking: people who are accustomed to seeing loved ones smoke are more likely to try it.
• Depression.
• Anxiety.
• Alcohol or illicit drug use.

Complications

Smoking causes numerous complications as it contributes to a wide range of diseases. The most frequent include:

• Lung, bronchial, oral, throat (larynx and pharynx), and tongue cancer.
• Acute myeloid leukemia, esophageal, stomach, bladder, kidney, liver, pancreatic, colon, rectal, and cervical cancer.
• Pulmonary emphysema: alveolar damage leading to impaired gas exchange.
• Chronic bronchitis: persistent inflammation of the bronchi.
• Pneumonia.
• Chronic obstructive pulmonary disease (COPD): airway inflammation and obstruction causing difficulty breathing.
• Coronary artery disease: narrowing and blockage of arteries supplying blood to the heart.
• Atherosclerosis: hardening of arteries with loss of flexibility.
• Myocardial infarction.
• Aortic aneurysm: localized dilation of the aortic wall due to vessel wall weakness.
• Blood clots.
• Chronic asthma.
• Stroke: interruption of blood flow to the brain.
• Type 2 diabetes.
• Kidney disease.
• Cataracts.
• Macular degeneration: damage to the central retina, causing loss of central vision and fine detail perception.
• Periodontitis: gum infection.
• Tooth loss: usually a consequence of periodontitis.
• Infertility: tobacco negatively affects both oocyte and sperm quality.
• Osteoporosis: increased bone porosity, resulting in fragility.
• Premature menopause.
• Premature aging.

Smoking during pregnancy may cause:

• Miscarriage.
• Preterm birth.
• Low birth weight.

Prevention

Smoking prevention begins by avoiding tobacco; the goal is to prevent consumption of the first cigarette. Children should grow up in smoke-free environments where they do not see family members smoke. A healthy lifestyle, including a balanced diet and regular physical activity, is also recommended.

Which Specialist Treats Smoking?

Smoking is treated by the Pulmonology specialty.