Up to four in ten cancer cases worldwide may be preventable, according to a new study published in Nature Medicine, offering a potentially transformative understanding of cancer risk and prevention. Researchers identified 30 preventable cancer causes, with tobacco, infections, and alcohol consumption ranking among the most significant contributors.
The study, which analyzed 18.7 million new cancer cases reported in 2022, estimated that 37% were attributable to preventable risk factors. The proportion varied by sex, with approximately 30% of cancer cases in women and 45% in men linked to these factors. The findings underscore the potential for substantial reductions in cancer incidence through targeted prevention strategies.
“This shifts the conversation from cancer being driven mainly by genetics or poor luck to one where prevention plays a central role,” explained Amar Rewari, M.D., chief of radiation oncology for Luminis Health. “Nearly 40% of cancers globally are linked to factors we already understand and, at least in theory, can change.”
The leading preventable causes identified in the study include tobacco smoking, alcohol consumption, obesity, insufficient physical activity, smokeless tobacco leverage, air pollution, ultraviolet radiation, and infection. The relative importance of these factors differed geographically. In higher-income countries, lifestyle factors such as smoking, obesity, and alcohol consumption were more prominent, while in lower-resource settings, infection-related cancers posed a greater threat.
Specifically, the study highlighted the prevalence of stomach cancer diagnoses associated with H. Pylori infections in Japan and Korea, and liver cancer diagnoses linked to hepatitis B and C infections in Africa. Increased access to vaccines and screenings has already demonstrated a reduction in these types of cancers, though significant challenges remain in ensuring equitable access to preventative care.
According to a fact sheet from the National Cancer Institute, a standard alcoholic drink in the United States contains 14.0 grams (0.6 ounces) of pure alcohol, typically found in 12 ounces of beer, 5 ounces of wine, or 1.5 ounces of 80-proof liquor. The Dietary Guidelines for Americans recommend that adults who choose to drink alcohol do so in moderation – limiting consumption to two drinks or less in a day for men and one drink or less in a day for women, on days when alcohol is consumed.
The Centers for Disease Control and Prevention (CDC) emphasizes that all types of alcoholic beverages – including red and white wine, beer, and liquor – increase cancer risk. Alcohol can disrupt cell cycles, increase chronic inflammation, and damage DNA, potentially leading to uncontrolled cell growth. It also increases the absorption of carcinogens, particularly when combined with tobacco use.
The study’s findings reinforce the importance of tailored prevention strategies. “This highlights the need for prevention strategies that are tailored to where people live and the risks they face, rather than a one-size-fits-all approach,” Dr. Rewari said.
Dr. Rewari stressed the importance of everyday choices, stating, “Avoiding tobacco in all forms remains the single most important step to reduce cancer risk. Limiting alcohol, staying physically active, and maintaining a healthy weight can also make a meaningful difference over time.” He also emphasized the value of vaccinations against hepatitis B and HPV as powerful cancer prevention tools.
While individual actions are crucial, Dr. Rewari noted that broader policies supporting clean air, safer workplaces, and access to preventative care are equally important. “Cancer prevention works best when people are supported by healthier environments and policies, not left to do it all on their own.”
The National Cancer Institute reports that alcohol consumption is the third leading preventable cause of cancer in the United States, after tobacco and obesity, accounting for an estimated 96,730 cancer cases in 2019.