Cancer being down to genes 'is a myth'

People should stop believing cancer is just down to “bad luck” or their genes and look to their own lifestyle, an expert said today.

People should stop believing cancer is just down to “bad luck” or their genes and look to their own lifestyle, an expert said today.

An unhealthy diet and poor lifestyle – such as a lack of exercise and being overweight – causes three times as many cases of cancer as genetics, said Dr Rachel Thompson, science programme manager for the World Cancer Research Fund (WCRF).

Evidence suggests that only about 5% to 10% of all cancers result from specifically inherited genes.

Meanwhile, 39% of the most common cancers, including breast and bowel, could be prevented through following a good diet, exercising and keeping weight under control.

Dr Thompson said: “It’s important to dispel the myth that cancer is just down to genes.

“The evidence shows that an unhealthy diet and low activity levels cause three times more cancer cases than genes.

“It could possibly be even more than this, if only 5% of cancers are as a result of our genes, then an unhealthy diet and lifestyle could cause eight times more cancer cases.

“If people do have a family history, then this is important information for them personally, but overall this inherited genetic predisposition is uncommon.

“Specific genes for breast and bowel cancer have been identified, but these are rare and account for a very small percentage of cancer cases, whereas more than a third of the most common cancers could be prevented by following a healthy diet, being physically active and maintaining a healthy weight.”

According to scientists at the WCRF, people who inherit these genes have a higher than average risk of cancer, but they will not certainly go on to develop the disease.

Even those whose genes mean they are at a higher than average risk can help cut their chances of developing cancer by eating a healthy diet with lots of fruits, vegetables and wholegrains, reducing their salt and alcohol intake and avoiding processed meats.

Dr Thompson said: “When you add not smoking into the healthy lifestyle mix, this 39% becomes even higher.

“In fact those who have inherited genes should pay closer attention to their lifestyle as there is probably still a lot they can do to reduce their risk.

“Many think that inherited genes or simply bad luck are the only factors in cancer development and it’s about time that myth was laid to rest.

“It is clear that choosing a healthy diet and being more physically active are important ways to help prevent many cancers.”

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