Does Marital Status Affect Cancer Risk? New Research Findings

Adults who have never been married may face a significantly higher risk of developing cancer compared to those who are or have ever been married, according to a study published April 8, 2026, in Cancer Research Communications.

The research, conducted by the Sylvester Comprehensive Cancer Center at the University of Miami Miller School of Medicine, analyzed health data from approximately four million cancer cases across 12 U.S. States. The study focused on adults ages 30 and older, comparing individuals who had never married with those in the ever-married category, which includes people who are currently married, separated, divorced, or widowed.

Researchers identified a consistent pattern across all age and racial groups: never-married adults had significantly higher cancer rates. Specifically, never-married men showed a 68 percent higher likelihood of developing cancer, while never-married women had an 83 percent higher incidence than their ever-married counterparts.

Higher Rates of Preventable Cancers

The most pronounced differences were observed in cancers linked to preventable risk factors, including smoking, alcohol use, reproductive history, and infections.

• Never-married men had about five times the rate of anal cancer compared to ever-married men.
• Never-married women had nearly three times the rate of cervical cancer.
• Liver cancer rates were approximately 2.3 times higher and lung cancer rates were 2.1 times higher for all never-married adults.
• Colorectal cancer rates were about two times higher in never-married women.
• Ovarian and uterine cancers were about 2.4 times higher in never-married women.
• Breast cancer rates were 1.7 times higher and prostate cancer rates were 1.5 times higher overall among the never-married.

The study noted that the gap in cancer risk was even more pronounced in adults aged 55 or older. The finding that the association was stronger in women challenges previous assumptions that the health benefits of marriage primarily favored men.

Social and Behavioral Drivers of Risk

Researchers emphasized that marriage itself does not prevent cancer, but rather serves as a marker for a variety of social, economic, and behavioral factors. Paulo Pinheiro, PhD, a professor of cancer epidemiology at the Miller School Department of Public Health Sciences and co-author of the study, noted that marriage reflects ties that influence risk through multiple mechanisms.

One primary factor is the influence of partners on health behaviors. The authors suggested that ever-married individuals may be more likely to engage in healthier habits, such as reduced tobacco and alcohol consumption. This is reflected in the higher rates of lung and esophageal cancers found among those who never married.

Exposure to infections also played a role. Both anal and cervical cancers are strongly linked to the human papillomavirus (HPV). Dr. Pinheiro stated that a higher number of sexual partners can increase exposure to cancer-causing viruses, which may explain the higher rates of these specific cancers in the never-married group.

Reproductive factors further contributed to the disparity. Pregnancy and childbirth provide protective effects against ovarian and endometrial cancers, and married women are statistically more likely to have children.

social support systems can impact healthcare engagement. Partners often help individuals navigate the healthcare system, ensuring they receive necessary screenings and preventive care. Loneliness, conversely, has been associated with poorer health behaviors and lower engagement with medical services.

Study Limitations and Context

Because the research was observational, it does not prove that marriage causes a reduction in cancer risk. It also relied on legal marital status, which does not account for the quality of the relationship or cohabitation without legal marriage.

Although marital status is an important predictor of health, being married doesn’t automatically protect you.

Bert Uchino, PhD, professor of psychology at the University of Utah Health

Dr. Uchino noted that other research indicates poor marriage quality can be associated with negative health outcomes.

Recommendations for Cancer Prevention

Medical experts involved in the study’s discussion clarified that these findings are not a prescription to get married, but rather a signal for unmarried adults to be more vigilant about their health.

Frank Penedo, PhD, associate director for population sciences at the Sylvester Comprehensive Cancer Center, stated that those who are not married should pay extra attention to cancer risk factors and stay up to date on screenings.

To reduce cancer risk regardless of relationship status, health experts recommend the following:

• Maintain regular doctor visits and adhere to recommended cancer screenings and vaccinations, including the HPV vaccine.
• Avoid smoking and limit the use of alcohol.
• Adopt protective habits, including a healthy diet, regular physical exercise, and safer sex practices.
• Develop strong social connections and support systems beyond marriage or primary partnerships.