Nearly half of cancer cases in men could be prevented

New data from Cancer Research UK answers the question that men have been asking for a long time: just how many cancers are truly preventable.

The answer, in men anyway, appears to be nearly half.

Yes, the research published in a supplement to the British Journal of Cancer suggests that about 45% of cancers in men are caused by one or more of 14 lifestyle and environmental risk factors. (In women it's around 40%.)

Smoking is far and away the most important lifestyle factor causing 23% of cancers in men and 15.6% in women (nearly one in five of all cancers).

In other words, cancer is not just about bad luck or bad genes.

Professor Max Parkin, the author of the study, said: ‘Many people believe cancer is down to fate or "in the genes" and that it is the luck of the draw whether they get it. Looking at all the evidence, it’s clear that around 40% of all cancers are caused by things we mostly have the power to change.

‘We didn’t expect to find that eating fruit and vegetables would prove to be so important in protecting men against cancer. And among women we didn’t expect being overweight to have a greater effect than alcohol.’

Of course many cancers have multiple causes. It’s not all down to us. Some environmental factors are controlled by others such employers. Overall, Cancer Research UK estimate one in 25 cancers is linked to occupation and one in 33 to infections.

One in three cancers caused by fags, booze, poor diet and being overweight

It is estimated that the big four - tobacco smoking, dietary factors, drinking alcohol and bodyweight - accounted for 106,845 or 34% (one in three) of all cancer in men and women in 2010.  This is based on predicted numbers of cancer cases in 2010, using UK incidence figures for the 15-year period from 1993 to 2007.

Dr Harpal Kumar, Cancer Research UK’s chief executive, said: ‘Leading a healthy life doesn’t guarantee that a person won’t get cancer but this study shows that healthy habits can significantly stack the odds in our favour.’

The full list of 14 risk factors are:

• tobacco,
• lack of fruit and vegetables,
• being overweight or obese,
• alcohol,
• excessive sun exposure and sunbeds,
• occupation,
• infections,
• radiation,
• lack of physical exercise,
• lack of breast feeding,
• hormones,
• red and processed meat,
• lack of fibre and too much salt.

Cancer Research UK point out that ‘as more than one risk factor may contribute to each individual cancer a statistical method which accounts for the overlapping risk factors has been used to calculate the proportion of cancers attributed to various risk factors’.