Most people know that smoking is extremely harmful and causes many serious diseases, but some people - particularly those hooked on nicotine - can't fight the temptation to light up.
The video below is a stark reminder of how harmful smoking is to the lungs.
Filmed in a lab, it shows a healthy pink lung in comparison to an organ blackened by smoke.
While the healthy lung expands when filled with air, the decreased capacity of the smoker’s lung means it barely changes. A lower capacity enables a smaller amount of oxygen to reach the bloodstream.
As well as lung cancer and heart disease, smokers are also susceptible to bronchitis. Smoke particles damages the cilia: hair-like structures inside the organs which catch irritants and excess mucus. Heavy smokers destroy the cilia, making them prone to infections.
On 9 March, the British Heart Foundation and other organisations mark No Smoking Day to draw attention to the dangers of the habit.
A new study released to co-incide with the day has found that those who try to quit smoking are now using e-cigarettes more than other methods such as nicotine gum and skin patches.
More than one million smokers in England used the devices when trying to quit last year, according to academics at University College London (UCL).
13 ways to help prevent cancer
13 ways to help prevent cancer
Stopping smoking. This notoriously difficult habit to break sees tar build-up in the lungs and DNA alteration and causes 15,558 cancer deaths a year
Avoiding the sun, and the melanoma that comes with overexposure to harmful UV rays, could help conscientious shade-lovers dodge being one of the 7,220 people who die from it
A diet that is low in red meat can help to prevent bowel cancer, according to the research - with 30 grams a day recommended for men, and 25 a day recommended for women
Foods high in fibre, meanwhile, can further make for healthier bowels. Processed foods in developed countries appear to be causing higher rates of colon cancer than diets in continents such as Africa, which have high bean and pulse intakes
Two servings of fruit and three servings of vegetables a day were given as the magic number for good diet in the research. Overall, diet causes only slightly fewer cancer deaths than sun exposure in Australia, at 7,000 a year
Obesity and being overweight, linked to poor diet and lack of exercise, causes 3,917 deaths by cancer a year on its own
Dying of a cancer caused by infection also comes in highly, linked to 3,421 cancer deaths a year. Infections such as human papilloma virus - which can cause cervical cancer in women - and hepatitis - can be prevented by vaccinations and having regular check-ups
Cutting back on drinks could reduce the risk of cancers caused by alcohol - such as liver cancer, bowel cancer, breast cancer and mouth cancer - that are leading to 3,208 deaths a year
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Sitting around and not getting the heart pumping - less than one hour's exercise a day - is directly leading to about 1,800 people having lower immune functions and higher hormone levels, among other factors, that cause cancers
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Hormone replacement therapy, which is used to relieve symptoms of the menopause in women, caused 539 deaths from (mainly breast) cancer in Australia last year. It did, however, prevent 52 cases of colorectal cancers
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Insufficient breastfeeding, bizarrely, makes the top 10. Breastfeeding for 12 months could prevent 235 cancer cases a year, said the research
Oral contraceptives, like the Pill, caused about 105 breast cancers and 52 cervical cancers - but it also prevented about 1,440 ovarian and uterine (womb) cases of cancer last year
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Taking aspirin also prevented 232 cases in the Queensland research of colorectal and oesophagal cancers - but as it can also cause strokes, is not yet recommended as a formal treatment against the risk of cancer
They estimated that 2.6 million of England's eight million smokers tried to quit last year. Two fifths of those who tried to quit used an e-cigarette compared with 26 per cent who used a licensed nicotine products.
”We estimate that e-cigarettes have probably helped around 20,000 smokers to quit each year, that wouldn't have otherwise," said Robert West, professor of health psychology at UCL.
Mike Knapton, associate medical director at the British Heart Foundation, added: “Although e-cigarettes are much less harmful than smoking cigarettes, there is no doubt that more research is needed into the potential long term effects of the use of them.
“This unique study shines a light on just how popular e-cigarettes have become as an aid for smokers trying to quit and we need to listen to what is helping people the most on their path to a smoke free life.”Reuse content