Effects of smoking and tobacco

Within 10 seconds of your first puff, the toxic chemicals in tobacco smoke reach your brain, heart and other organs. Smoking harms almost every part of your body and increases your risk of many diseases. Smoking also affects how you look and feel, your finances and the people close to you.

What happens in your body

When you smoke, harmful chemicals enter your lungs, move into your blood stream and spread through your body. They can:

  • reach your brain, heart and other organs within 10 seconds of your first puff
  • go everywhere your blood flows, causing damage anywhere they go.

Did you know?

Even if you don’t inhale tobacco smoke, you still absorb harmful chemicals through the lining of your mouth.

How you become addicted

The nicotine in tobacco is highly addictive. It makes your brain release a chemical called dopamine. Dopamine is a ‘feel good’ chemical that:

  • makes you feel happy
  • helps you to concentrate
  • gives you more energy.

But this effect doesn’t last long.

As the nicotine levels in your body fade, your brain craves more dopamine. The longer you have been smoking, the more dopamine you need to feel good. You become dependent on nicotine to create this feeling.

Once you are dependent on nicotine, without it you will have withdrawal symptoms. You may find it difficult to concentrate or feel nervous, restless, irritable or anxious.

These 2 things – nicotine dependence and nicotine withdrawal – make you want to smoke more. You have become addicted to tobacco.

How tobacco damages your body

Tobacco contains over 100 dangerous chemicals. These chemicals can damage your body in many ways. For example:

  • Nicotine narrows your veins and arteries. This can
    • damage your heart by forcing it to work faster and harder
    • slow your blood and reduce oxygen to your feet and hands.
  • Carbon monoxide deprives your heart of the oxygen it needs to pump blood around your body. Over time, your airways swell up and let less air into your lungs.
  • Tar is a sticky substance that coats your lungs like soot in a chimney. This damages your lungs and is known to cause lung disease, which can make it harder to breathe. 
  • Phenols paralyse and kill the hair-like cells in your airways. These means the cells cannot sweep clean the lining of your airways and protect you against infections.
  • Tiny particles in tobacco smoke irritate your throat and lungs and cause ‘smoker’s cough’. This makes you produce more mucus and damages lung tissue.
  • Ammonia and formaldehyde irritate your eyes, nose and throat.
  • Cancer-causing chemicals make your cells grow too fast or abnormally- which can result in cancer cells. Smoking is known to cause at least 16 types of cancer.

How tobacco affects the way you look

Smoking tobacco can:

  • cause yellow-brown stains on your fingers, tongue and teeth
  • increase your risk of tooth loss, damaged gums and bad breath
  • make your skin saggy and give you early wrinkles
  • make your hair lose its natural shine.

Health effects

Smoking is the leading cause of preventable disease and death in Australia.

If you smoke, you:

  • reduce your life expectancy and your quality of life
  • increase your risk of many conditions and diseases as well as of dying prematurely.

It can be a long time before smokers get a smoking-related condition or disease. Because of this, some people believe it won’t happen to them.

In fact, up to ⅔ of long-term smokers will:

  • die of a smoking-related disease
  • have their life cut short by about 10 years on average, compared to non-smokers.

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

Increased risk of conditions and diseases

Did you know?

Tobacco use is the only risk factor that contributes to 4 of the main types of non-communicable diseases: cardiovascular disease, cancer, chronic lung disease and diabetes.


Smoking causes most lung cancers and can cause cancer almost anywhere on the body. This includes the mouth and nose, throat and voice box, oesophagus, blood cells, liver, stomach, kidney, pancreas, mucinous ovary, ureter, cervix, colon and bladder.

Breathing problems and chronic respiratory conditions

Smoking is the main cause of chronic obstructive pulmonary disease (COPD), a serious, progressive and disabling condition that limits airflow in the lungs. Active smoking also worsens asthma in active smokers and is associated with an increased risk for asthma in adolescents and adults.

Heart disease, stroke and blood circulation problems

Smoking is major cause of cardiovascular disease, such as heart disease and stroke, and cardiovascular disease is one of the major causes of death for both men and women. Smoking increases the risk of blood clots, which block blood flow to the heart, brain or legs. Some smokers end up having their limbs amputated due to blood circulation problems caused by smoking.

People who smoke have more heart attacks than people who don’t smoke. They are also more likely to die from a heart attack at a younger age, even in their 40s.


Smoking causes type 2 diabetes. The risk of developing diabetes is 30 to 40% higher for active smokers compared to non-smokers. Smoking can also worsen some of the health conditions related to type 1 diabetes, such as kidney disease, eye disease and poor circulation which can lead to gangrene.


Smoking weakens your immune system so you’re more likely to get bacterial and viral infections.

Smoking reduces blood flow in your body, so wounds can take longer to heal.

Dental problems

Smoking increases the risk of gum diseases, tooth loss and tooth sensitivity. Once a person has gum damage, smoking also makes it harder for their gums to heal.

People with dental problems can find it harder to chew and swallow, which can lead to poor nutrition and further health issues.

Hearing loss

Smoking reduces blood flow to the inner ear. It can also cause irritation and swelling to the Eustachian tubes (the tubes which connect the back of the nose with the middle ear) resulting in pain and infection.

Smokers may lose their hearing earlier than a non-smoker.

Vision loss

Smoking damages the eye and can lead to macular degeneration – the main cause of blindness in Australia.

Fertility problems

Smoking can make it more difficult to fall pregnant and affect sperm quality. Find out more about smoking, vaping and tobacco and pregnancy.

Osteoporosis and menopause

Smoking is a risk factor for osteoporosis – a condition that weakens your bones and makes them more likely to break – and in women, may result in early menopause compared to a non-smoker.

What the numbers say

  • The most recent available estimates show that almost 20,500 Australians died from tobacco use in 2018. This equates to one tobacco-related death every 26 minutes.
  • Up to ⅔ of deaths in current smokers can be attributed to smoking and current smokers are estimated to die an average of 10 years earlier than non-smokers.

Effects on those around you

As a smoker, you can affect the health of other people when they breathe in your second-hand smoke. This means they’re breathing in the same toxic and cancer-causing chemicals that you are.

Find out about:

Financial effects

Smoking is expensive. To work out how much you could save if you stopped smoking, try the I Can Quit calculator. The numbers add up over a year.

If you smoke a pack of cigarettes a day, you could be spending more than $15,000 a year on cigarettes.

Reducing the effects

There is no safe level of smoking.

To reduce your risk, the best option is to quit smoking. You’ll feel the health benefits almost straight away.

Date last updated:

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