Smoking has a wide variety of health effects and can affect just
about every organ in the body. But one of the organs that is most
directly affected is the lungs. This is maybe not surprising as this is
the organ in direct contact with cigarette smoke.
The lungs are
organs of respiration. They are designed to carry air that contains
oxygen and pass this oxygen to the blood stream. Everybody has two
lungs that are divided into lobes.
When somebody starts smoking
this causes irritation of the cells lining the air tubes within the
lungs (the bronchi and bronchioles). One of the body's basic responses
to this is to produce mucus. This mucus can reduce the diameter of the
airtubes making it more difficult to breathe. Have you heard of a
'smoker's cough'? This is when a smoker coughs up this mucus.
In a
healthy person, there are cells lining the lungs and upper respiratory
tract that have small hair-like projections called cilia present. These
beat to move dust and debris out of the lungs. They are a bit like the
lung's own broom sweeping team. Smoking kills these cells so that their
cleaning function is no longer carried out. Dust and particles can
then accumulate which is one of the reasons that smokers often complain
of respiratory diseases.
One of the gases in cigarette smoke is
carbon monoxide. This gas interferes with the process of oxygenation of
blood in the lungs. In fact if you inhale too much carbon monoxide you
will suffocate and die. This gas is present in car exhaust fumes and
is responsible for the deaths of many people each year using this as a
form of suicide.
The air sacs in your lungs where oxygen is passed
to the blood are called alveoli. These have a very large surface area -
about the size of a tennis court. Every time that you smoke you kill
some of these alveoli. These structures can't grow back, so once they
are destroyed, that's it. Is it any wonder that smokers find it
difficult to breathe due to minor exertion, such as walking up stairs?
The
long-term effect of smoking on the lungs is quite well documented.
Cancer of the lungs is largely due to smoking. It is estimated that 87%
of cases of lung cancer in the US are smoking related. Smoking is the
primary cause behind a condition called COPD (Chronic Obstructive
Pulmonary Disease). Patients with this condition find it very difficult
to breathe because their airways have become so obstructed.
By
Paul Elms
