Most lung cancer preventable, says UNSW study

New research from UNSW suggests that most lung cancer can be prevented by the adoption of a healthy lifestyle.

Examples of ‘healthy lifestyle’ behaviour include giving up smoking, eating more fruit and being physically active.

UNSW’s Centre for Big Data Research in Health pooled seven Australian cohort studies of 370,000 people. The project found that tobacco smoking continued to be responsible for most lung cancer in Australia. It remains the leading cause of cancer death in Australia and worldwide.

UNSW Senior Research Fellow Dr Maarit Laaksonen said, “More than three out of four lung cancers are caused by ever smoking. Current smoking is responsible for more than half of lung cancers and past smoking for nearly a quarter.”

The study showed that the risk of lung cancer risk remained raised for 40 years after stopping smoking. It halved roughly every 10 years.

Of the 74,600 lung cancers attributable to current smoking in Australia in the next 10 years, 25,400 could be avoided if all current smokers were to quit.

The harms from smoking persist for decades. The findings emphasised the importance of plain packaging and other tobacco-control activities that discouraged smoking.

People who smoke fewer than 20 cigarettes a day make up a large proportion of future lung-cancer patients – even though they might not class themselves as “heavy” smokers.

The researchers also found that eating two “serves” (about 300g) of fruit every day may reduce the lung-cancer burden by eight per cent.

Doing 150 minutes of “moderate” or 75 minutes of “vigorous” physical activity each week may reduce the lung-cancer burden by 16 per cent.

At present, about 16 per cent of Australians smoke. But roughly half of all Australians (whether smokers or not) aren’t eating enough fruit. Nearly three-quarters don’t get enough exercise.

Overall, the UNSW study concludes, at least four in five lung cancers appear preventable through changed lifestyles.

“The majority of Australians could benefit from increasing their fruit intake and physical activity,” Dr Laaksonen said. “But for those who currently smoke, stopping smoking should be the first course of action.

“Our findings strongly support the dual importance of preventing the uptake of smoking and assisting quitting, in all Australians and especially in those with the highest burden.”