A new study has revealed cancer is not a cause of ‘bad luck’, but a product of a person’s environment, and other external influences.

Published in the journal Nature, up to nine in 10 cancers are the byproduct of things like smoking, drinking, sun exposure, and air pollution. The researchers used four methods to conclude only 10-30% of cancers come down to natural body functions or ‘luck’.

The ‘bad luck hypothesis’ has been the accepted cause for years, as previous research suggested random cell mutations were the catalyst.


Scientists now believe that outside influences have a far greater impact, meaning many cancers may be more preventable than previously thought. Between 70 and 90% of cancers wouldn’t occur if we lived in an ideal setting, unaffected by environment. This is unrealistic, but shows how much these extrinsic factors affect the body.

“It’s not true that most cases of cancer ‘just happen’, and that there is nothing we can do to prevent them occurring,” said Kate Allen from the World Cancer Research Fund.

“Our research has shown that many cancers are caused by external factors, and that there are changes that we can all make to our lifestyles to significantly reduce our risk of cancer.”

The study was done by Stony Brook University in New York. The scientists didn’t buy a study published earlier in the year that claimed cancer was inevitable in some circumstances, driven by random mistakes in cell division which are completely outside of our control.

If random mutations were to blame, there would be far fewer cases of cancer than there actually are, was the initial hypothesis by Stony Brook researchers.


“Here we provide evidence that intrinsic risk factors contribute only modestly to cancer development,” said Yusuf Hannun of Stony Brook University. “The rates of mutation accumulation by intrinsic processes are not sufficient to account for the observed cancer risks.”

Many health professionals and experts said the analysis study is ‘pretty convincing’.

Dr. Emma Smith, from Cancer Research UK, said: “While healthy habits like not smoking, keeping a healthy weight, eating a healthy diet and cutting back on alcohol are not a guarantee against cancer, they do dramatically reduce the risk of developing the disease.”