Nearly 40% of cancer cases worldwide could be prevented through lifestyle changes, environmental improvements, and vaccinations. This striking revelation comes from a new global analysis conducted by the World Health Organization (WHO) and its International Agency for Research on Cancer (IARC).
Released just ahead of World Cancer Day on 4 February, the study highlights that approximately 7.1 million new cancer cases in 2022—representing 37% of the global total—were linked to 30 preventable causes. This data underscores an enormous opportunity for governments to reduce the global health burden by addressing specific, avoidable risks.
The Top Culprits: Tobacco, Infections, and Alcohol
The study, which drew data from 185 countries and 36 different cancer types, identifies tobacco as the single greatest preventable threat. It is responsible for 15% of all new cancer cases globally.
However, for the first time, researchers included nine cancer-causing infections in their assessment. These infections now rank as the second leading preventable cause, accounting for 10% of cases, followed by alcohol consumption at 3%.
Three specific types of cancer account for nearly half of all preventable cases globally:
- Lung Cancer: Primarily driven by tobacco smoking and air pollution.
- Stomach Cancer: Largely attributable to Helicobacter pylori infections.
- Cervical Cancer: Overwhelmingly caused by the Human Papillomavirus (HPV).
The Gender Gap in Preventable Cancer
The research reveals a significant disparity between men and women. Men face a substantially higher burden, with 45% of new cases deemed preventable, compared to 30% for women.
In men, the primary driver is smoking (23%), followed by infections (9%) and alcohol (4%). For women, infections are the leading preventable cause (11%), followed by smoking (6%) and a high Body Mass Index (3%). Consequently, prevention strategies must be tailored to address these differing risk profiles.
Regional Variances and Economic Factors
The prevalence of preventable cancer fluctuates wildly depending on the region. These differences often reflect a country’s level of socioeconomic development and the strength of its national health policies.
East Asia: Records the highest burden for men, with 57% of cases being preventable.
Sub-Saharan Africa: Sees the highest preventable burden for women at 38%, largely due to infectious diseases.
Latin America and the Caribbean: Reports the lowest preventable burden for men at 28%.
A Call for Coordinated Action
“This is the first global analysis to show how much cancer risk comes from causes we can prevent,” says Dr André Ilbawi, WHO Team Lead for Cancer Control. Experts argue that addressing these factors requires more than just individual effort; it necessitates coordinated action across sectors such as education, energy, transport, and labour.
Effective strategies include:
- Strong tobacco and alcohol regulations.
- Widespread vaccination against HPV and Hepatitis B.
- Improved air quality and safer workplace environments.
- Promoting healthier food and physical activity.
Q&A: Understanding Cancer Prevention
Which infections cause cancer?
The study identifies nine specific infections. Key examples include HPV (causing cervical and other cancers), Helicobacter pylori (linked to stomach cancer), and Hepatitis B (linked to liver cancer).
How does air pollution affect cancer rates?
Air pollution is a significant contributor to lung cancer. Improving air quality through better energy and transport policies can directly lower the number of new diagnoses.
Why is the preventable rate higher in men? The higher rate in men is primarily due to significantly higher levels of tobacco use and alcohol consumption compared to women globally.
Frequently Asked Questions (FAQ)
- Can all cancers be prevented?
No. While the study shows that 40% are preventable, the remaining 60% are often linked to genetics, ageing, or unknown factors that are currently beyond our control.
- What is the most effective way to prevent cervical cancer?
Vaccination against HPV and regular screening are the most powerful tools available to eliminate cervical cancer as a public health threat.
- Is “High BMI” a major cancer risk?
Yes. High Body Mass Index (BMI) is listed as one of the 30 preventable causes and is a leading risk factor for women, contributing to 3% of their total new cancer cases globally.
- When is World Cancer Day?
World Cancer Day is observed every year on 4 February to raise awareness and encourage prevention, detection, and treatment.
- How many countries were included in this WHO study?
The researchers analysed data from 185 countries and looked at 36 different types of cancer.