One Million Annual Cancer Deaths in China Attributable to Lifestyle Factors

CC BY 2.0. Mstyslav Chernov/Wikimedia Commons

More than half the country's cancer deaths in 2013 were caused by potentially modifiable behaviors like smoking and diet.

As Benjamin Franklin famously quipped, "in this world nothing can be said to be certain, except death and taxes." To that I'd add, "and a desire to avoid cancer." It's surely a certain and universal thing; nobody wants cancer. Yet it is a disease that can be attributed to lifestyle factors over which we have control. And now, new research from a multi-agency team of scientists led by Farhad Islami, M.D., Ph.D. of the American Cancer Society sheds some light on just how much cancer we might be able to avoid through preventive initiatives aimed at the devastating disease.

With 4.3 million new cancer cases and 2.8 million cancer deaths estimated to occur each year in China, it is the country's leading cause of death. It's awful, it's painful, it's heartbreaking, it strains the healthcare system and it's expensive – and the numbers are expected to increase in the coming decades, explains the new study, because of an aging population as well as "changes in lifestyle that increase cancer risk, such as excessive calorie intake and physical inactivity."

The report concludes that effective public health interventions to get rid of or reduce exposure from risk factors – they looked at ever-smoking, second-hand smoking, alcohol drinking, low fruit/vegetable intake, excess body weight, physical inactivity, and infections – can have a significant impact on reducing the cancer burden there. (And elsewhere I might add; these problems aren't exclusive to China.)

Using current data from nationally representative surveys and cancer registries, the researchers found the following:

• 717,910 (52 percent) of cancer deaths in men and 283,130 (35 percent) in women in 2013 were attributable to the risk factors included in the analysis.

• Among both sexes combined, around 996,000 (almost half of all cancer deaths) were attributable to the studied risk factors.

The greatest attributable proportions of cancer deaths in men were for:

• ever-smoking (26 percent) – note that China is the world’s biggest tobacco market
• hepatitis B (HBV) infection (12 percent)
• low fruit/vegetable intake (7 percent)

In women the largest contributors were:

• HBV infection (7 percent)
• low fruit/vegetable intake (6 percent)
• second-hand smoke exposure (5 percent)

Sadly, the research didn't even take into consideration other factors that could have made the numbers even more grim. "Our analysis likely underestimates the number of cancers attributable to modifiable risk factors because we were not able to include all potentially modifiable risk factors, notably indoor air pollution from using coal for cooking and heating, which is a major risk factor for lung cancer in women in China," says Dr. Islami.

It all feels tragic, but the bright side resides in a single word: modifiable. Hopefully the research will lead to measures and more public awareness about the lifestyle factors involved and what can be done to reduce risk.

The report appears in Annals of Oncology.