Smoking is the leading cause of lung cancer, which causes more deaths
than any other form of cancer. Smoking affects both smokers and people nearby,
through second-hand smoke.
Why is smoking hazardous?
There are three major reasons smoking is dangerous:
1. "The nicotine effect"
- Nicotine is one of the major chemical components in
the tobacco leaves used to make cigarettes.
Nicotine reaches the brain just a few seconds after smoking
begins. The rich blood supply in the lungs picks up any chemical in
the air very rapidly.
- Nicotine causes the nervous system to stimulate the
release of adrenaline into the blood. When adrenaline increases in
the blood, it causes the heart to beat faster, the blood vessels to
constrict (to become more narrow), and the breathing rate to
increase. Nicotine constricts blood vessels directly too.
Constricted vessels create a large resistance for the heart to pump
against. Nicotine also constricts the blood vessels in the heart
and can promote heart attacks.
- Initially nicotine gives the brain a boost, but
when the effect wears off, fatigue and depression set in.
- Nicotine is one of the most addictive drugs known.
Just a few puffs can create cravings for nicotine in some people. And
young people are more likely to get addicted quickly than older
2. Lung irritation
In addition to nicotine, the burning of
tobacco produces other hazardous materials. Some of them are:
Acetone - a solvent, used in nail polish
remover, for example.
Carbon Monoxide - an odorless, colorless poisonous gas
that is lethal in large doses. In smaller doses, carbon monoxide causes
increased heart rate and shortness of breath. Carbon
monoxide attaches itself to the red blood cells and blocks their ability to carry oxygen.
Formaldehyde - a preservative for dead bodies. In cigarette
smoke, this chemical is a known carcinogen
and causes respiratory
Hydrogen Cyanide - short-term exposure can lead to headaches,
dizziness, nausea and vomiting.
Lead - a highly toxic metal, capable of causing
serious damage to the brain, kidneys, nervous system and red blood
Cigarette smoke contains many organic tars that irritate
delicate lung tissue. As the irritation increases, the lung linings begin to
break down, reducing the efficiency of the lungs. One common
disease resulting from the break down of the lung linings is emphysema.
- In emphysema, the alveoli over inflate because they are trying to let
more oxygen into the blood. This over inflation reduces the
elasticity of the alveoli and makes them less efficient.
- As emphysema progresses the lungs become less elastic and can no longer clear the air out of the lungs.
- When the air remains in the lungs for a longer period
of time than normal, the oxygen is depleted and carbon dioxide builds
- When carbon dioxide builds up in the lungs, the alveoli
swell and may even burst open. This causes tissue damage and can
lead to scar tissue.
- The lungs do not exchange old air for new air efficiently.
3. Lung cancer- Smoking is the leading cause
of lung cancer in the United States. Lung cancer causes more deaths
in the United States than any other type of cancer.
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Similar problems occur with snuff and chewing tobacco.
The nicotine effect is the same. The irritation and cancer effects can
be the same, except it is the mouth that is affected instead of the lungs.
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