More than 40% of cancers 'preventable'

7th December 2011 - Around 134,000 cases of cancer diagnosed each year in the UK are potentially preventable because they are either caused by people's lifestyle or the environment around them, a major report has concluded.

The study says that more than 100,000 of these cancers - equivalent to a third of all those diagnosed in the UK each year - are caused by smoking, unhealthy diets, alcohol and people being overweight.

Not just in the genes

The review of cancer and lifestyle, published in a supplement to the British Journal of Cancer, is the most comprehensive yet undertaken and adds further weight to the argument that cancer is not 'all about genes'.

It shows that, overall, 45% of all cancers in men and 40% in women could be prevented.

Smoking emerges as the number one risk factor for both sexes, causing 23% of cancers in men and 15.6% in women. However, some of the findings surprised the researchers. For instance, they found that eating fruit and vegetables was more important in protecting men against cancer than they expected; among women they had not expected to find that being overweight was a greater cancer risk factor than alcohol.

"I was a bit surprised that alcohol came out rather lower than expected, at 4% or 5%," study author Professor Max Parkin tells BootsWebMD. "Somehow we'd got it into our heads that this was a much more serious risk," he says.

Overall, Professor Parkin, a Cancer Research UK epidemiologist at Queen Mary, University of London, says the results were broadly in line with expectations.

Six top risk factors

Of the 158,700 cancers diagnosed in men each year:

• Tobacco is responsible for 36,500 cases (23%)
• Lack of fruit and vegetables is responsible for 9,600 cases (6.1%)
• Occupation, such as exposure to asbestos is responsible for 7,800 cases (4.9%)
• Alcohol is responsible for 7,300 cases (4.6%)
• Being overweight and obese is responsible for 6,500 cases (4.1%)
• Excessive sun exposure and sunbeds are responsible for 5,500 cases (3.5%)

Of the 155,600 cancers diagnosed in women each year:

• Tobacco is responsible for 24,300 cases (15.6%)
• Being overweight and obese is responsible for 10,800 cases (6.9%)
• Infections, such as HPV, are responsible for 5,800 cases (3.7%)
• Excessive sun exposure and sunbeds are responsible for 5,600 cases (3.6%)
• Lack of fruit and vegetables is responsible for 5,300 cases (3.4%)
• Alcohol is responsible for 5,100 cases (3.3%)

Other risk factors for cancer that were taken into account are radiation, lack of physical exercise, lack of breast feeding, hormones, eating red and processed meat, lack of fibre and too much salt.