A new study by the American Cancer Society (ACS) found that a high number of cancer cases and deaths in adults 30 and older were due to factors that could potentially be prevented, like cigarette smoking and poor diet.
The findings revealed that 40 per cent of cases and about half of all cancer deaths in the United States are attributed to factors that could be controlled.
Researchers analysed the incidence and mortality of 30 types of cancer in relation to 18 modifiable risk factors.
“A large number of cancer cases and deaths in the United States are attributable to potentially modifiable risk factors, indicating the potential to substantially reduce the cancer burden through broad and equitable implementation of preventive initiatives,” Dr Farhad Islami, lead author of the study, told Euronews Health.
The factors included in the study ranged from cigarette smoking, excess body weight, and drinking alcohol, to the consumption of red and processed meat, low intake of fruits and vegetables, dietary fiber, and dietary calcium.
Other factors were physical inactivity, ultraviolet (UV) radiation, and cancer-causing infections, such as human papillomavirus (HPV).
Cigarette smoking was identified as the leading risk factor and was responsible for 20 per cent of all cancer cases and 30 per cent of cancer deaths in the US.
It was followed by excess body weight and alcohol consumption.
For cancer cases alone, the next factors included UV radiation, physical inactivity, HPV infection, low fruit and vegetable consumption, and processed meat consumption.
For cancer deaths, the critical factors in order of importance were physical inactivity, low fruit and vegetable consumption, UV radiation, HPV infection, and processed meat consumption.
Islami also explained that even if a factor strongly causes cancer, if it's rare, it will result in only a few cancer cases overall.
However, a common factor with a weaker effect can lead to a higher number of cancer cases.
According to Islami, understanding the number of cancer cases and deaths caused by preventable factors is useful in setting better initiatives in cancer prevention and increasing public awareness about risk factors.
To lower the risk of cancer, he suggested that people can take action on an individual level by avoiding or reducing exposure to these risk factors.
Additionally, on a wider level, increasing fair access to preventive healthcare and raising awareness about prevention methods could also be useful.
“In case of smoking, for example, persons who currently smoke can reduce their health risks by quitting. Healthcare providers can also provide guidance for quitting,” he said.
Recommendations to reduce the risk of getting or dying from cancer include avoiding the use of any tobacco products and for smokers to quit.
Other measures include following dietary guidelines, staying physically active, maintaining a healthy body weight, and limiting excessive sun exposure.
Keeping up with necessary vaccinations, such as for the Hepatitis B virus (HBV) and HPV, was also recommended.
“Vaccination at the recommended time can substantially reduce the risk of chronic infection, and consequently, cancers associated with these viruses,” Dr. Ahmedin Jemal, senior author of the study, said in a statement.