' Even if your risk is low for lung cancer, it may be high for heart disease.

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In lung cancer, there are even more caveats to the data.

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Prior work has shown that the precise type of bacteria responsible for lung infections or even the presence of stomach cancer could be discerned in the breath.

BBC: Exhaled breath is unique fingerprint

Even if you think that is a correct societal judgement, as was pointed out on the Today Programme, many thousands of lung cancer sufferers gave up smoking years even decades before diagnosis.

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Even nonsmoker Lizzie Middleton, a 65-year-old survivor of lung and colon cancer, agrees.

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Jean King said recent research shows that even if you quit at the age of 60 you can reduce your risk of lung cancer.

BBC: Passive smoke greater in the home

Here is perhaps an even more chilling number: according to the ONS more than 70% of lung-cancer sufferers are dead in less than a year after diagnosis.

BBC: How under-funded is lung cancer research?

In the case of lung cancer, studies suggest that beta carotene supplementation may actually increase your risk, even if you don't smoke.

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Lung cancer, however, has a much lower survival rate, so remains the biggest killer, even though falls in smoking rates have reduced its incidence.

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