Lifestyle choices are responsible for 9 out of 10 cancers, a recent study featured in the journal Nature has shown.
Experts at Stony Brook University in New York conducted this research, starting from the hypothesis that tumors appear not just because of accidental genetic mutations, and that other factors may be more significant.
This idea was based on the fact that the number of cancer diagnoses in recent years is overwhelmingly elevated, and cellular mutations don’t normally have such a high prevalence.
Researchers then reviewed studies that had involved people leaving countries with low cancer rates, and immigrating to regions with much more frequent cancer diagnoses.
They noticed that such individuals eventually also suffered from malignant tumors, at the same percentage as the one encountered among the rest of the population which they had recently become part of.
As explained by Kevin McConway, professor of applied statistics at the Open University in England, between 70 and 90% of all cancerous tumors are actually triggered by factors in the environment, which could be prevented entirely.
Basically, if one could eliminate aspects such as harmful habits (drinking, smoking, sedentary lifestyles, inadequate diets) or other external stimuli (radiation, pollution etc.) it would be possible to reduce the incidence of cancer by as much as 90%.
More precisely, three quarters of all colon cancer cases are associated with bad eating habits, such as favoring a high-calorie diet rich in fats and processed meat, instead of opting for more fruit and vegetables.
Similarly, about 86% of all skin cancers are linked to excess amounts of UV radiation, as a result of prolonged exposure to the sun or frequent use of sunbeds.
In addition, approximately three quarters of all tumors affecting the larynx, mouth, throat, nose, salivary glands and lips are related to alcohol use and cigarette smoking.
According to Song Wu, study lead author and assistant professor of applied mathematics and statistics at Stony Brook University, while certain rare types of cancer may indeed be dependent exclusively on genetic factors, the vast majority of cancers stem from adopting routines that progressively damage the body, to the point of no return.
Therefore, more emphasis should be placed on these extrinsic risk factors which are within the individuals’s control, so as to reduce the likelihood of developing cancer in the future.
Researchers admit that their results may be dismissed by some, who might find it difficult to believe that kicking bad habits such as smoking or indoor tanning would have such a protective effect when it comes to keeping malignant tumors at bay.
Prior studies had indicated that cancer may be to a great extent a question of bad luck, as genes within cells mutate haphazardly, without the individual being able to halt this process in any way.
One such research, conducted by scientists at Johns Hopkins University and presented in January 2015, had indicated that 65% of all tumors are caused by indiscriminate errors occurring when DNA replicates, while the rest are indeed the result of genetic predispositions and environmental stimuli.
Given the fact that in some parts of the body cells divide more quickly and frequently, this would explain why the lifetime risk of developing a certain type of tumor is higher than that encountered for other types.
For instance, the likelihood of suffering from lung cancer is of 1 in 14, whereas for brain cancer the probability is much lower, estimated at 1 in 166.
Image Source: Pixabay