Shocking statistics: Experts estimate 40% of cancer cases are preventable

The ynet report revealed that the primary risk factor identified is smoking, responsible for nearly one in five cancer cases and almost one-third of cancer deaths. Other contributing factors for about 40% of people over 30 include alcohol consumption, physical inactivity, diet, and infections.

Professor Alona Zer-Koch, director of medical oncology at Rambam Hospital, notes that "lung cancer is likely the most preventable cancer, with more than 80% of cases linked to smoking. Additionally, some cases not directly caused by smoking may be related to passive smoking or air pollution, both of which are preventable."

The risk of developing lung cancer for a non-smoker is less than 1 in 100, while a heavy smoker faces a risk of 1 in 3 or 4, underscoring the strong connection between smoking and lung cancer. Zer-Koch adds that recent studies indicate a link between lung cancer and air pollution, while assessing the impact of passive smoking can be more challenging due to underreporting.

Preventable risk factors for lung cancer also include occupational exposure, such as for those working with engines or asbestos, as well as individuals exposed to dust and polishing agents. "Smoking not only contributes to lung cancer but also increases the risk for other cancers, including those of the nose, mouth, esophagus, and bladder," she explains. "Other cancers, such as skin tumors from sun exposure, are also preventable."

The study identified additional risk factors, including being overweight, alcohol consumption, physical inactivity, poor diet, and infections like the human papillomavirus (HPV). Being overweight is the second leading cause of cancer after smoking, linked to about 5% of new cases in men and nearly 11% in women. This factor is associated with over a third of deaths from various cancers, including those of the gallbladder, esophagus, liver, and kidneys.

In total, researchers analysed 18 modifiable risk factors across 30 types of cancer and found that in 2019, these lifestyle factors were associated with more than 700,000 new cancer cases and over 262,000 deaths.

The findings indicate that certain cancers are more preventable than others. The risk factors studied accounted for over half of new cancer cases in 19 of the 30 types examined. In 10 types of cancer, modifiable risk factors were linked to at least 80% of new cases, including over 90% of melanoma cases associated with ultraviolet radiation and almost all cervical cancers linked to HPV infection, which can be prevented through vaccination.

Zer-Koch emphasizes that "HPV vaccination significantly reduces the risk of cervical cancer and is also believed to lower the risk of other cancers associated with the virus, such as penile tumors and cancers of the anus, mouth, and pharynx."