Can Cancer Be Prevented?

Question: I live in a developing (lower income) country, and we dread to hear the word “cancer.” We don’t have the modern cancer treatments that wealthy countries have. Can lifestyle decrease the amount of cancer in our country?

Answer: Yes—lifestyle can decrease the incidence of cancer. Prevention is not just possible—it is essential.

Cancer is one of the most feared diagnoses worldwide. It affects families, communities, and health systems across every continent. Yet there is an important and hopeful truth: Many cancers are preventable. Modern research, including the recent landmark study “Global and Regional Cancer Burden Attributable to Modifiable Risk Factors,” by H. Fink and colleagues, shows that more than one third of cancers globally are linked to risk factors that people and societies can change, especially through lifestyle. In 2022 there were about 18.7 million new cancer cases worldwide. Of these, about 7.1 million (37.8 percent) were linked to modifiable risk factors.[1]

Put simply, nearly four out of every 10 cancers could be avoided if key risks were reduced. Other large global studies support this finding, estimating that more than 40 percent of cancer deaths are also linked to preventable causes.[2]

The leading preventable risk factors include tobacco use (the single biggest contributor), infections such as human papilloma virus (HPV) and hepatitis, alcohol use, unhealthy diet and obesity, physical inactivity, and air pollution and environmental exposures. These are not rare or unusual risks. They are part of daily life in many communities, which is why prevention must involve both individuals and society. Treatment for cancer has improved greatly, but it is often expensive, complex, and not equally available around the world. Prevention, on the other hand, is often simpler, cheaper, and more effective. Preventing cancer also reduces the suffering. It means fewer hospital visits, fewer families facing loss, and healthier communities overall.

Treatment for cancer has improved greatly, but it is often expensive, complex, and not equally available around the world.

Cancer does not affect all countries in the same way. There are clear differences between low- and middle-income countries (LMICs) and high-income countries.

1. Infection-related cancers are higher in LMICs. In many lower-income regions infections play a major role in such cancers as cervical cancer (caused by HPV), liver cancer (linked to hepatitis B and C), and stomach cancer (linked to Helicobacter pylori). These cancers are more common where access to vaccines, screening, and treatment is limited. A global study found that infections account for a significant share of preventable cancers globally, especially in lower-income settings.

2. Lifestyle-related cancers are rising in middle-income countries. As countries develop, lifestyles often change. Diets may include more processed foods, physical activity decreases, and obesity rates rise. This leads to a pattern sometimes called the “cancer transition” to more lifestyle-related cancers such as breast cancer, colorectal cancer (alarmingly increasing in younger adults globally), and prostate cancer.

3. Tobacco remains a global problem. Smoking is the leading cause of preventable cancer everywhere, with tobacco accounting for about 15 percent of all cancer cases worldwide. Patterns of tobacco use differ. Smoking rates are falling in high-income countries, while still increasing in some low- and middle-income countries.

4. Access to prevention and care differs. People in high-income countries are more likely to have cancer screening (e.g., mammograms, colonoscopies), vaccination (HPV, hepatitis B), and early diagnosis and treatment. In contrast, many LMICs face limited health-care infrastructure, less cancer screening, late diagnoses, and fewer treatment options. These factors lead to higher death rates even when overall cancer incidence is lower.

Understanding the main causes helps guide prevention.

Tobacco: Smoking causes cancers of the lung, throat, mouth, bladder, and more. It is the largest preventable cause of cancer globally.

Infections: Vaccines and treatment can prevent infection-related cancers. Intentional and careful implementation of HPV vaccine significantly prevents cervical cancer. The hepatitis B vaccine helps prevent liver cancer; this is particularly beneficial in regions in which hepatitis B is endemic and often transmitted from mother to child at birth or during early childhood.

Alcohol: Alcohol increases the risk of cancers of the liver, breast, and digestive system.

Diet and body weight: Poor diet and obesity are linked to several cancers, including colon and breast cancer.

Physical inactivity: Regular movement helps reduce cancer risk and improves overall health.

Environment: Air pollution, ultraviolet radiation (sun exposure), and workplace exposures to smoke and fumes may also cause cancer.

The good news is that many of these risks can be reduced with practical, everyday steps. Individuals and society need to bridge the knowledge-behavior disconnect by turning knowledge into action. Prevention does not require perfection—it requires consistent, small actions.

Prevention begins with awareness, grows through community action, and succeeds with sustained commitment.

Below are realistic and doable steps for individuals around the world.

1. Avoid tobacco completely. Do not start smoking. If you smoke, seek help to quit. Avoid secondhand smoke. Even quitting later in life reduces cancer risk.

2. Avoid alcohol. There is no safe level of alcohol intake regarding its role in carcinogenesis, and in general. Avoidance of alcohol means lower cancer risk.

3. Choose healthier foods. Eat more fruits and vegetables. Reduce processed and red meats. Limit sugary drinks and highly processed foods. Healthy eating does not need to be expensive—local, seasonal foods are often best.

4. Stay physically active. Aim for at least 30 minutes of activity most days. Walking, working out in the gym, swimming, gardening, or household work all count. Movement is powerful medicine.

5. Maintain a healthy weight. Balance food intake and activity. Small changes over time can make a big difference. Reaching and maintaining ideal weight is the work of a lifetime!

6. Protect yourself from infections. Get vaccinated (HPV, hepatitis B where available). Seek treatment for infections early.

7. Protect your skin. Avoid strong midday sun. Wear hats and protective clothing, and use sunscreen when possible.

8. Participate in screening. Cervical screening (Pap test or HPV test) and breast screening where available. Mammography for women starts between 40 and 50 years old, in consultation with their physician and risk of breast cancer. Colon cancer screening, stool testing for occult blood (blood that cannot be seen with the naked eye), and colonoscopy testing should start at 45 years old, earlier if there is a family history and in consultation with one’s physician. Early detection saves lives.

Prevention is not only an individual responsibility. Communities and governments can also play a key role by implementing the following:

• Reduce tobacco use by enforcing smoke-free public spaces, increasing taxes on tobacco, and providing quitting support.

• Improve vaccination access—for example expanding HPV and hepatitis B vaccination programs, targeting schools and community centers.

• Promote healthy environments by creating safe spaces for walking and exercise, improving air quality, and ensuring access to clean cooking fuels.

• Support healthy food systems by encouraging local production of healthy food and crops, and reducing the availability of unhealthy processed foods.

• Strengthen health systems, thereby increasing access to screening and early diagnosis. Encourage and sponsor young people to train as health-care workers and focus on providing safe and affordable treatment.

A Hopeful Conclusion

Cancer will always be a serious disease, but it is not only a matter of chance or fate. Science shows that more than one third of cancers can be prevented, and possibly even more with strong public health action.2 This is a powerful message of hope. By reducing tobacco use, improving diet, increasing physical activity, preventing infections, and creating healthier environments, millions of lives can be saved.

Prevention begins with awareness, grows through community action, and succeeds with sustained commitment. Every step—no matter how small—moves us closer to a world with fewer cancers and healthier lives for all.

It is important for us as a church never to judge nor be critical of individuals who have diseases we may feel are preventable. Remember, genetics and heredity play a significant role in the causation of disease, including cancers. Our role is to support those who are facing the challenge of cancer and to extend grace-filled love and care to all (Luke 6:37)!

[1] H. Fink et al., “Global and Regional Cancer Burden Attributable to Modifiable Risk Factors to Inform Prevention,” Nature Medicine 32, no. 5 (2026): 1306-1315, https://doi.org/10.1038/s41591-026-04219-7.

[2] K. Tran et al., “The Global Burden of Cancer Attributable to Risk Factors, 2010-2019: A Systematic Analysis for the Global Burden of Disease Study 2019,” The Lancet 400, no. 10352 (2022): 563, https://doi.org/10.1016/S0140-6736(22)01438-6.