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Understanding your habit – why you smoke

When quitting smoking, finding the right motivation to quit can make all the difference in your success. Whether that means learning more about the various health risks associated with smoking, the effect smoking can have on those around you, or exactly how much it costs you to keep up the habit, this is the time to find that motivation to quit — and stay quit.

On this page, we’re going to look more closely at why people smoke, and why quitting smoking is hard. We’ll look at what smoking does to your body, to then find out the various health effects of quitting smoking. We’ll also talk habits, helping you understand what makes you feel like smoking, so you can work on avoiding those triggers and change your habits over time.

What’s in a cigarette

Let’s start with what’s in a cigarette

There are more than 7,000 harmful chemicals in a cigarette. Some real nasty stuff too. The same kind of chemicals you’d find in places like your tool shed, under the bonnet of your car, or contained within cleaning products under your sink. One thing’s for sure, they don’t belong in your body. Check out what’s in a cigarette. You’ll be surprised.

See what’s inside

What happens when you smoke?

When you smoke, those harmful chemicals enter your lungs, and then spread through your body. Accessing your bloodstream, the chemicals can go everywhere your blood goes, causing harm to every part of your body, reaching your brain, heart and other organs just 10 seconds from when you first inhale.

Even if you don’t inhale, you will still absorb chemicals through the lining of your mouth, and from there, into your bloodstream.

How does nicotine addiction work?

So, why do you keep smoking, knowing that it’s causing you harm? Alongside all those other chemicals, it’s the nicotine within cigarettes that keeps you smoking them. Highly addictive, nicotine works by stimulating reward centres in the brain, releasing dopamine and creating temporary feelings of happiness or calm, giving you more energy and helping you concentrate.

The problem is these effects don’t last long. Between cigarettes, nicotine levels in your body fade, which leads your brain to crave more dopamine. And, the longer you have been smoking, the more dopamine you need to feel good. This leads you to become dependent on nicotine, and without it, you will experience withdrawal symptoms.

Not smoking then makes it difficult to concentrate, or can leave you feeling anxious, irritable, restless or even nervous. It is this nicotine dependence, combined with nicotine withdrawal, that makes you want to smoke more – creating a cycle that’s hard to break out of. In other words, you are addicted. It’s recommended that you use nicotine replacement products or medication when quitting.

What smoking does to your body

By smoking, you reduce not only your life expectancy, but your quality of life. And while you may not feel many of the negative health effects straight away, you are putting yourself at risk for any number of smoking-related diseases.

In fact, up to two-thirds of long-term smokers die of a smoking-related disease, and have their life cut short by about 10 years on average, compared to non-smokers.

  • Nicotine narrows your veins and arteries, slowing your blood and reducing oxygen to your feet and hands, and damaging your heart by forcing it to work harder.
  • Tar coats your lungs, much like soot in a chimney.
  • Carbon monoxide deprives your heart of the oxygen it needs to pump blood around your body, which eventually results in your airways swelling up, letting less air into your lungs.
  • Ammonia and formaldehyde aggravate your eyes, nose and throat.
  • Phenols kill the hair-like cells in your airways, which means they can no longer clean the lining of your airways to protect them against infections.
  • Tiny particles in tobacco smoke irritate your throat and lungs, making you produce more mucus and damaging lung tissue.
  • Cancer-causing chemicals make your cells grow abnormally, which can result in cancer cells.

Medical issues commonly associated with smoking include cancer, heart disease and stroke, diabetes and chronic respiratory conditions, as well as dental problems, loss of hearing and vision, fertility problems, osteoporosis and infections caused by a weakened immune system.

There is also evidence to suggest smoking has a negative impact on mental health, with some studies showing that smoking is associated with increased rates of depression, anxiety, panic attacks, schizophrenia and suicide attempts.

Habit and routines

Aside from the addiction itself, certain habits can also make quitting smoking hard. Perhaps you usually smoke when you have a cup of coffee or tea. When you quit, your brain remembers that habit, creating a craving for a cigarette whenever you have a cuppa.

Identifying these habits—or triggers—can help you manage them, allowing you to find alternatives to smoking, or perhaps changing your routine or finding a distraction.

Some suggestions include:

Usual habits: Coping strategies:
When you wake up Have a shower and plan the day ahead.
With coffee Change your drink type or take the time to experience its full flavour. Consume your drink in a new location.
When driving Listen to your favourite music when driving. Make your car smoke-free and remove cigarettes from sight.
After work Go for a walk with friends.
After dinner Chew gum or call a friend.
When watching TV Fiddle with a stress ball.
Just before bed Have a warm drink or watch a funny video.
With alcohol Avoid alcohol as much as possible in the first few weeks. Have a non-alcoholic beverage – hold it in the hand you usually hold your cigarette.
As a reward Buy a copy of your favourite magazine and enjoy reading and flipping through it.
When you’re with another smoker Hold a water bottle in your hand and have regular sips.
When working on your computer at home Move the room around or put your computer in another room. Take regular sips of water.

Other triggers

Overall, understanding what makes you smoke can help you avoid it when you quit. Aside from the habits mentioned above, you may find your feelings or emotions are connected to smoking, so you reach for a cigarette for comfort when you’re sad or angry, or for something to do when you’re bored or wanting to cover up uncomfortable feelings.

Certain social situations may also be a trigger. Going to a party or social gathering, going to the pub, or having friends over may become difficult to deal with when you initially quit. Not only does your brain create cravings as a result of remembering you smoking in those situations, you may also be surrounded by others who are smoking.

Make a quit diary

Creating a quit diary can help you better manage habits and triggers. To do this, each time you have a cigarette or experience a craving, note down the date and time, what you’re doing, what you’re feeling, and how strong the craving is.

This should help you identify what your triggers are and where your habits lie, and from there you can find ways to work around them.

What quitting can do for you

While the effects of smoking may seem somewhat overwhelming, you can turn things around by quitting smoking. You might be surprised just how quickly things start to change.

  • After 12 hours, almost all the nicotine will be out of your system, and most by-products will be gone within five days.
  • After 24 hours, the level of carbon monoxide in your blood will have dropped considerably, allowing your body to take in and use oxygen more efficiently.
  • After two days, your sense of smell and taste will start to return.
  • After two months, blood flow to your hands and feet will have improved.
  • After one year, your risk of heart disease will have dropped significantly.
  • After 10 years, your risk of lung cancer will have halved.

See the health benefits

How the body repairs

Need help?

Quitting smoking is hard. But you don’t have to go it alone. Talk to your friends and family, discuss it with your GP, or call Quitline to speak to a counsellor for expert advice, encouragement, and tailored quit smoking support — including personalised strategies, how to manage cravings or withdrawals, and products that can help.

Sign up now to start your quit journey Register for support


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