| Of the seven million worldwide cancer deaths | | | | roles in all income levels and regions. |
| reported in 2001, 35 percent were | | | | |
| attributable to nine well-known behavioral | | | | Worldwide, the nine risk factors caused 1.6 |
| and environmental risk factors, according to | | | | million cancer deaths among men and 830,000 |
| an analysis published in The Lancet. | | | | among women. Smoking alone is estimated to |
| | | | have caused 21 percent of deaths from cancer |
| Researchers from the Harvard School of Public | | | | worldwide. |
| Health (HSPH) and a network of collaborators | | | | |
| made the calculation by estimating mortality | | | | In high-income countries, these nine risks |
| for 12 types of cancer linked to the nine | | | | caused 760,000 cancer deaths. Smoking, |
| risk factors in seven World Bank regions for | | | | alcohol, and overweight and obesity were the |
| that year. | | | | most important causes of cancer in these |
| | | | nations. |
| They also looked at how the risks, and the | | | | |
| cancers they cause, were distributed over the | | | | In low- and middle-income regions, the nine |
| regions of the world. This is the first | | | | risks caused 1.67 million cancer deaths. |
| assessment of the role of health risks in | | | | Smoking, alcohol consumption, and low fruit |
| cancer deaths globally and regionally. | | | | and vegetable intake were the leading risk |
| | | | factors for these deaths. |
| Risk Factor Analysis | | | | |
| | | | Sexual transmission of human papillomavirus |
| The researchers analyzed data from the | | | | is the leading risk factor for cervical |
| Comparative Risk Assessment project and World | | | | cancer in women in low- and middle-income |
| Health Organization databases to determine | | | | countries, particularly in Sub-Saharan Africa |
| the level of risk factors in different world | | | | and South Asia, where access to cervical |
| regions, and separately for men and women. | | | | screening is also limited. |
| | | | |
| They also considered how hazardous each risk | | | | Among low- and middle-income regions, Europe |
| factor might be. The analysis covered all | | | | and Central Asia had the highest proportion |
| high-income countries together, and separated | | | | of death from cancer from the nine risk |
| low-income and middle-income countries into | | | | factors studied; 39 percent of 825,000 cancer |
| geographical regions: East Asia and Pacific, | | | | deaths in the low- and middle-income |
| South Asia, Europe and Central Asia, Latin | | | | countries of Europe and Central Asia were |
| America and Caribbean, Middle East and North | | | | caused by these risks. |
| Africa, and Sub-Saharan Africa. | | | | |
| | | | The effects were even larger among men; one |
| The nine risk factors: | | | | half of cancer deaths among men in the low- |
| | | | and middle-income countries of Europe and |
| - overweight and obesity | | | | Central Asia were caused by these nine risks. |
| | | | |
| - low fruit and vegetable intake | | | | Behaviors and Environments |
| | | | |
| - physical inactivity | | | | "These results clearly show that many |
| | | | globally important types of cancer are |
| - smoking | | | | preventable by changes in lifestyle behaviors |
| | | | and environmental interventions," comments |
| - alcohol use | | | | Majid Ezzati, senior author of the study and |
| | | | assistant professor of international health |
| - unsafe sex | | | | at HSPH. |
| | | | |
| - urban air pollution | | | | "To win the war against cancer, we must focus |
| | | | not just on advances in biomedical |
| - indoor smoke from household use of coal | | | | technologies, but also on technologies and |
| | | | policies that change the behaviors and |
| - contaminated injections in healthcare | | | | environments that cause those cancers," he |
| settings | | | | adds. |
| | | | |
| Alcohol, Smoking Play Large Roles | | | | The study, "Causes of cancer in the world: |
| | | | comparative risk assessment of nine |
| More than one in every three of the seven | | | | behavioral and environmental risk factors," |
| million deaths from cancer worldwide were | | | | was funded by the National Institute on Aging |
| caused by these nine potentially modifiable | | | | and by the Disease Control Priorities |
| risk factors (2.43 million), the researchers | | | | Project. |
| found, with alcohol and smoking playing large | | | | |