Effects of Tobacco on Health

 

Effects of Tobacco on Health

Overview

Tobacco is one of the leading preventable causes of disease and death worldwide. It adversely affects nearly every organ system of the human body. Tobacco is consumed in smoking forms (cigarettes, bidis, cigars, hookah) and smokeless forms (gutkha, khaini, zarda, chewing tobacco, snuff). Both forms are harmful and addictive because of nicotine. Tobacco use is associated with cardiovascular diseases, respiratory diseases, cancers, reproductive disorders, and numerous other health problems.

1. Tobacco: Definition and Forms

Definition

Tobacco is obtained from the leaves of the plant Nicotiana tabacum and Nicotiana rustica. It contains several harmful chemicals, the most important being nicotine.

Common Forms of Tobacco

Smoking Tobacco

• Cigarettes
• Bidis
• Cigars
• Pipe tobacco
• Hookah (water pipe)

Smokeless (oral) Tobacco

• Gutkha
• Khaini
• Zarda
• Paan (betel leaves) with tobacco
• Snuff

In India, smokeless tobacco use is particularly common and contributes significantly to oral cancers.

2. Harmful Constituents of Tobacco

Tobacco smoke contains more than 7,000 chemicals, including hundreds of toxic substances and many carcinogens (cancer-causing agents).

Important Harmful Chemicals

Chemical	Harmful Effect
Nicotine	Addiction, increased heart rate and blood pressure
Carbon monoxide	Reduces oxygen transport by blood
Tar	Contains carcinogens; damages lungs
Benzene	Causes cancer
Formaldehyde	Respiratory irritation
Arsenic	Toxic and carcinogenic
Cadmium	Kidney damage
Hydrogen cyanide	Damages respiratory epithelium
Nitrosamines	Strong carcinogens

 

3. Nicotine and Addiction

What is Nicotine?

Nicotine is a highly addictive alkaloid present in tobacco.

Mechanism of Addiction

1. Nicotine reaches the brain within seconds after inhalation.
2. It stimulates release of dopamine.
3. Dopamine produces pleasure and reward sensations.
4. Repeated exposure causes dependence.
5. Withdrawal symptoms develop when tobacco use stops.

Withdrawal Symptoms

1. Irritability
2. Anxiety
3. Depression
4. Difficulty concentrating
5. Craving for tobacco
6. Sleep disturbances

4. Effects of Tobacco on the Respiratory System

The respiratory system is among the most severely affected organ systems.

A. Damage to Respiratory Epithelium

Normally, cilia remove dust and microbes from air passages.

Tobacco Causes:

• Paralysis of cilia
• Increased mucus production
• Accumulation of toxic substances
• Increased respiratory infections

B. Chronic Bronchitis

Definition

Persistent inflammation of bronchi associated with excessive mucus production.

Symptoms

• Chronic cough
• Sputum production
• Breathlessness

C. Emphysema

Definition

Destruction of alveolar walls leading to enlarged air spaces.

Consequences

• Reduced respiratory surface area
• Poor oxygen exchange
• Severe breathlessness

D. Chronic Obstructive Pulmonary Disease (COPD)

COPD includes:

• Chronic bronchitis
• Emphysema

Symptoms

• Chronic cough
• Wheezing
• Breathlessness
• Reduced exercise tolerance

Tobacco use accounts for a large proportion of COPD-related deaths globally.

E. Lung Cancer

Why Does Tobacco Cause Lung Cancer?

Carcinogens in tobacco:

• Damage DNA
• Cause mutations
• Promote uncontrolled cell division

Smoking is the primary cause of lung cancer, and smokers have a dramatically higher lifetime risk than non-smokers.

Warning Signs

• Persistent cough
• Blood in sputum
• Chest pain
• Weight loss
• Breathlessness

5. Effects on the Cardiovascular System

Tobacco significantly increases cardiovascular morbidity and mortality.

Mechanisms

Nicotine Causes:

• Increased heart rate
• Increased blood pressure
• Vasoconstriction

Carbon Monoxide Causes:

• Reduced oxygen carrying capacity
• Increased workload on heart

Tobacco Also:

• Damages blood vessel walls
• Accelerates atherosclerosis
• Promotes clot formation

Major Cardiovascular Diseases

1. Coronary Artery Disease (CAD)

Blockage of coronary arteries supplying the heart.

Consequences

• Angina pectoris
• Heart attack (myocardial infarction)

Smokers are 2–4 times more likely to develop coronary heart disease.

2. Stroke

Reduced blood supply to brain due to:

• Clot formation
• Vessel blockage

Smoking substantially increases stroke risk.

3. Peripheral Arterial Disease

Narrowing of arteries supplying limbs.

Symptoms

• Leg pain during walking
• Poor wound healing
• Gangrene

6. Effects on the Oral Cavity

Especially important in India because of widespread smokeless tobacco use.

Tobacco Causes

Dental Problems

• Tooth discoloration
• Dental caries
• Bad breath

Gum Diseases

• Gingivitis
• Periodontitis
• Tooth loss

Oral Precancerous Lesions

• Leukoplakia (white patches)
• Erythroplakia (red lesions)
• Submucous fibrosis

Oral Cancer

Strongly associated with:

• Gutkha
• Khaini
• Pan with tobacco
• Smoking

Common Sites

• Tongue
• Buccal mucosa
• Lips
• Floor of mouth

India has one of the highest burdens of tobacco-related oral cancer.

7. Effects on the Digestive System

Disorders Caused by Tobacco

Peptic Ulcer Disease

Smoking:

• Increases acid secretion
• Delays ulcer healing

Gastrointestinal Cancers

Risk increases for:

• Esophageal cancer
• Stomach cancer
• Pancreatic cancer
• Colorectal cancer

Inflammatory Bowel Disease

Smoking contributes to several gastrointestinal disorders.

8. Effects on Reproductive Health

In Males

Smoking Causes:

• Reduced sperm count
• Reduced sperm motility
• Erectile dysfunction
• Infertility

In Females

Smoking Causes:

• Reduced fertility
• Menstrual irregularities
• Early menopause

9. Effects During Pregnancy

Tobacco use during pregnancy harms both mother and fetus.

Adverse Outcomes

Maternal Effects

• Placental abnormalities
• Pregnancy complications

Fetal Effects

• Miscarriage
• Stillbirth
• Premature birth
• Low birth weight
• Fetal growth retardation

Smoking during pregnancy is linked to fetal death and stillbirth.

10. Effects on Infants and Children

Children exposed to tobacco smoke are highly vulnerable.

Health Problems

Respiratory Disorders

• Bronchitis
• Pneumonia
• Asthma

Ear Problems

• Middle ear infections

Sudden Infant Death Syndrome (SIDS)

Children exposed to second-hand smoke show increased risk of respiratory illness and hospitalization.

11. Second-Hand Smoke (Passive Smoking)

Definition

Inhalation of tobacco smoke by non-smokers.

Sources

• Smoke exhaled by smoker
• Smoke from burning cigarette/bidi

Health Hazards

Adults

• Lung cancer
• Heart disease
• Stroke

Children

• Asthma
• Respiratory infections
• Ear infections

There is no safe level of exposure to second-hand smoke. It causes approximately 1.6 million deaths annually worldwide.

12. Effects on the Immune System

Smoking weakens immune defenses.

Consequences

Increased Susceptibility To:

• Tuberculosis
• Pneumonia
• Influenza
• Other respiratory infections

Tobacco use is associated with increased mortality from tuberculosis and lower respiratory infections.

13. Effects on Other Organ Systems

Eye Disorders

• Cataract
• Age-related macular degeneration
• Vision loss

Skin

• Premature aging
• Wrinkles
• Delayed wound healing

Bone Health

• Osteoporosis
• Increased fracture risk

Brain

• Increased risk of dementia
• Cognitive decline

Metabolic Disorders

• Increased risk of Type 2 Diabetes Mellitus

Smoking is recognized as a risk factor for diabetes and dementia.

14. Cancer Caused by Tobacco

Tobacco is responsible for approximately one-fourth of all cancer deaths worldwide.

Cancers Linked to Tobacco

Respiratory Tract

• Lung cancer
• Laryngeal cancer

Oral Cavity

• Lip cancer
• Tongue cancer
• Buccal mucosa cancer

Digestive System

• Esophageal cancer
• Stomach cancer
• Pancreatic cancer
• Colorectal cancer

Genitourinary System

• Kidney cancer
• Bladder cancer

Others

• Cervical cancer
• Liver cancer

15. Tobacco Burden in India

Important Facts

• Nearly 267 million adults in India use tobacco.
• India is the second largest consumer and producer of tobacco.

·        Tobacco causes approximately 1.35 million deaths annually in India.

16. Benefits of Quitting Tobacco

It is never too late to quit.

Health Improvements After Quitting

Time After Quitting	Benefit
20 minutes	Heart rate and blood pressure decrease
12 hours	Carbon monoxide levels normalize
2–12 weeks	Lung function improves
1–9 months	Coughing decreases
1 year	Heart disease risk drops significantly
5–15 years	Stroke risk approaches that of non-smokers
10 years	Lung cancer risk decreases markedly
15 years	Heart disease risk becomes similar to non-smokers

 

High-Yield Points

·       Nicotine is the addictive component of tobacco.

·       Tobacco smoke contains more than 7,000 chemicals. (World Health Organization)

·       Smoking is the major cause of emphysema.

·       Tobacco is the leading preventable cause of cancer.

·       Passive smoking is also harmful.

·       Smoking increases risk of COPD, coronary artery disease, stroke, and lung cancer.

·       Smokeless tobacco is strongly associated with oral cancer.

·       Smoking during pregnancy can cause miscarriage, stillbirth, and low-birth-weight babies.

·       Tobacco weakens immunity and increases susceptibility to respiratory infections.

·       Quitting tobacco at any age significantly reduces health risks.

Conclusion

"Tobacco affects almost every organ of the body, causing addiction, cancer, cardiovascular disease, respiratory disease, reproductive disorders, fetal harm, and premature death." (World Health Organization)