Why Give Up Smoking?

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So you’ve seen all the warnings about how smoking is so bad for you. But here’s the question: Why? What is it about smoking that is so dangerous? Let’s find out!

What's inside a cigarette?

A cigarette is usually made up of 3 parts:

First there is the cigarette filter, this is also known as the cigarette butt. Then there is the rolling paper which is wrapped around a tobacco blend. The tobacco blend is usually made up of dried and processed tobacco leaves and leaf stems.  The main plant used in the manufacture of tobacco is Nicotiana Tabacum.

So what happens once a cigarette is lit?

Well the tobacco blend contains over 7000 different chemicals. These chemicals are released in the form of small particles and gases.

Cigarette smoke then passes through the cigarette filter. The cigarette filter traps bits of partially burnt tobacco – this is also called tar. The cigarette filter is able to trap some but not all of the tar.

Tar is sticky and brown, resulting in that characteristic yellow stain. In addition to staining the smokers fingernails, it also moves into the mouth and stains the teeth, the inner part of the mouth and also the vocal cords. The vocal cords become irritated because of the tar, making people cough reflexively.

Down to the airways

Once cigarette smoke has passed through the upper airway, it then goes to the lower airway. The lower airway is lined by cilia. Cilia are tiny hair like projections that beat in order to move debris and bacteria out of the lung.

Hydrogen cyanide is a poisonous gas that works with tar in order to paralyse these cilia. With the cilia out of action, the cigarette smoke is able to move even deeper into the lung.

Multiple other cancer causing chemicals in tobacco such as Arsenic and Benzopyrene also coat the lining of the airways. This is where they significantly increase the risk of lung cancer.

With the main defence of the lungs paralysed, the cigarette smoke moves into the deepest part of the lung. This is the alveoli or the air sacs of the lung. Normally, this is where oxygen is exchanged for carbon dioxide using a transfer protein called haemoglobin. Haemoglobin then carries the oxygen to the rest of the body, where the body cells use it as fuel.


Carbon monoxide is a poisonous gas that is also found in cigarette smoke. Carbon Monoxide is a bully. It knocks off oxygen from haemoglobin and instead takes it’s place. The problem here is that the body can’t use carbon monoxide as fuel, so these (body) cells starve because of the lack of oxygen. These starving cells send out inflammatory 'SOS' signals. However this backfires because the increased inflammation leads to increased mucous production and narrowing of the airways, making it even more difficult to breathe.

The remaining chemicals in cigarette smoke are also absorbed into the bloodstream. This is an important event – the bloodstream is the highway to all the organs inside the body. Once these chemicals are absorbed into the bloodstream, there is no limit to the amount of damage they can cause and the damage from these chemicals is no longer contained to just the lungs.

Oxidising Chemicals

There are a large number of oxidising chemicals in cigarette smoke. These chemicals are highly reactive and can damage any type of body cells.

The first thing in sight for these chemicals are the blood vessels themselves – oxidising chemicals react with the lining of the blood vessels causing inflammation and fatty plaques. These fatty plaques narrow the blood vessels.

The oxidising chemicals also damage the vessels that supply the heart and brain with oxygen – if these critical vessels become blocked, then part of the heart muscle or the brain tissue can die. Death of the heart muscle is called a heart attack or a myocardial infarction and death of the brain tissue is called a stroke, and can often lead to permanent disability.

Metals such as Arsenic and radioactive compounds like Polonium continue to travel to the other organs of the body through the blood. They significantly increase of the risk of cancer other than lung cancer, for example, skin cancer, liver cancer, kidney cancer and even bladder cancer.


And finally, the one chemical to rule them all, Nicotine. None of the effects that I've mentioned earlier sound attractive. So why is it that people continue to smoke? It is the nicotine in cigarettes that make them so addictive.

Within 7 seconds of smoking a cigarette, Nicotine rich blood travels from the lungs to the brain. In the brain, the nicotine attaches to a class of receptor called the Nicotinic Acetylcholine receptors.

Once these receptors are activated, they release a flurry of brain messengers like dopamine, adrenaline and serotonin. This leads to the activation of the brain’s reward and alertness system. This is why some people report feeling more focussed and attentive after smoking a cigarette. Nicotine can also cause temporary feelings of relaxation, due to the increased level of serotonin in the brain

Nicotine only stays in the body for a few hours. It is broken down in the liver and expelled through the urine.

As soon as the Nicotine exits the body, the body misses the buzz of having these huge amounts of stimulating brain messengers rushing around. Cravings can begin just two hours after your last smoke. Signs of nicotine withdrawal include restlessness, anxiety, frustration, anger, and even insomnia.

Every time you light another cigarette, the effect of nicotine gets weaker, as your brain develops a tolerance to the drug. Now you’ll need even more Nicotine to get the same high, and cravings get even stronger. This forms the cycle of addiction.

Wait there's more...?

There are thousands of other chemicals in tobacco smoke – we've only touched the tip of the iceberg. At least another 250 are known to be harmful and 70 are known to initiate, cause or promote cancer.

Now imagine putting your brain and your body through this kind of rollercoaster, every few hours, every day for many years. In Australia, people who smoke, smoke on average 93 cigarettes per week. In a year, that's 4836 cigarettes, costing you as much money as 4 new iPhones.

Other than the increased risk in cancer, there are so many other long term effects of smoking. Things like breakdown of the alveoli wall which is also called emphysema, staining and wrinkling of the skin, loss of smell and taste, impotence, and the list just goes on...

Tobacco is the only legal drug that kills its users when used exactly as intended by its manufacturers.

In the US, the National Survey of Drug Use and Health found that over 95% of smokers started before the age of 21. It can be very difficult to overcome an addiction to nicotine, so the best thing you can do is to never pick up a cigarette in the first place.

So what's the good news?

Well, the number of smokers worldwide is decreasing and with the power of the internet, help for people who want to quit smoking is just at our fingertips.

With the combined effect of more informed younger people and stronger tobacco control laws, we may one day see a generation who are smoke free. And wouldn’t that be a monumental achievement for humanity.

If you are smoking and even thinking of quitting, you are halfway there. Make the decision today.


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