Why Doctors Think Cancer Is on the Rise in Millennial Women

Many people mistakenly believe that cancer is primarily a disease of aging, but new data from the American Cancer Society (ACS) reveals a troubling truth—cancer rates are increasingly affecting younger adults. Research published on January 21 reveals that approximately 80,000 young adults (ages 20–39) in the United States are diagnosed with cancer annually, making it the fifth leading cause of death in this age group. Despite past declines due to screening and HPV vaccination, cervical cancer rates in women aged 30–44 have risen by 11 percent from 2013 to 2021. Newsweek spoke to one of the contributing authors of the study, Tyler Kratzer, an associate scientist II in cancer surveillance research, along with multiple medical experts to understand why this is happening.

Why Are Cancer Rates Rising In Young People?

"The reasons why many cancers are increasing in young and middle-aged adults are not well understood but are at least partly driven by behavioral changes," Kratzer, who works for the ACS, said. Newsweek also discussed several factors that may contribute to the rising rates with Dr. Monique Gary, a breast surgical oncologist based in Pennsylvania, and Dr. Eric Winer, the director of Yale Cancer Center. "We're at a point where we need to challenge our understanding of cancer as simply a disease of aging," Gary told Newsweek.

Diet

Excess body weight—including overweight and obesity—is a significant risk factor for cancer. Research from the American Cancer Society estimates that it contributes to approximately 5 percent of cancer cases in men, 11 percent in women, and 7% percent of all cancer-related deaths in the U.S. Dietary choices also play a crucial role. Processed foods, particularly meats, have been linked to increased cancer risk, along with alcohol consumption. In 2019 alone, alcohol was associated with an estimated 96,730 cancer cases in the U.S.—42,400 in men and 54,330 in women. Over a decade, this amounts to nearly one million preventable cancer cases. According to the U.S. Department of Health and Human Services, breast cancer carried the highest burden, with 44,180 alcohol-related cases, accounting for 16.4 percent of all breast cancer diagnoses that year. "It is becoming increasingly clear that poor nutrition and unhealthy eating habits play a critical role in cancer development. Food is medicine, and we truly are what we consume," Gary said.

Environment

Research has also revealed that products we use and what we consume contain endocrine disrupters—chemicals that can interfere with the body's hormones. In this day and age, plastic can't be avoided, and these endocrine disrupters have been linked to cancer, as well. Gary explained that disruptions in the endocrine system can trigger inflammation, leading to conditions like insulin resistance, polycystic ovary syndrome (PCOS), and autoimmune disorders, which are increasingly linked to cancer. However, further research is needed to confirm causation.

Delayed Childbirth

Studies have found that American women are waiting until they are older to have children. Kratzer explained this change in reproductive patterns also influences cancer in women—but not men. Winer, the president and physician-in-chief of Smilow Cancer Hospital in New Haven, Connecticut, said: "Early puberty and never having children or having a first child after 30 are risk factors for breast cancer."

Sedentary Lifestyles

"We've also seen how sedentary lifestyles influence cancer risk," said Gary. Indeed, millennials spend over 60 hours per week sitting due to long commutes, desk jobs, and screen time, according to a study by scientists at the University of Colorado Boulder and the University of California, Riverside.

Young Mom, 34, Diagnosed With Cancer

With no family history of cancer, Katelyn Armstrong, from North Carolina, told Newsweek she was "shocked and confused" when a mammogram confirmed her diagnosis in 2021. She was 34 years old. "I cried for a week straight," she said, adding that while her doctor took her seriously, a technician initially reassured her that breast cysts are common in women her age. "I think that it is a form of them trying to make us feel calm, but it can feel like a false promise," she told Newsweek. "Luckily, my obstetrician did not dismiss me, but I know that this is a rare experience." Just weeks earlier, Armstrong had been in the best shape of her life, with no health concerns. But after feeling a marble-sized lump in her breast during a shower, she initially dismissed it as dense breast tissue. Panic set in when the lump didn't change, became hard and started burning. After six rounds of chemotherapy, a double mastectomy, and 12 rounds of immunotherapy, Armstrong has seen "no evidence of disease" for three years as of May. "I'm not medically cancer-free," she noted, as she continues taking hormone therapy and an anti-estrogenic medication for an unspecified period.

Should Cancer Screening Guidelines Be Updated For Younger Women?

Screening tests detect cancer early, often before symptoms appear, improving treatment outcomes. However, most screenings for average-risk individuals start at age 45, with cervical cancer screening beginning at 25. As a result, many cancers are discovered through self-detection. Gary told Newsweek: "Eighty percent of breast cancers detected in younger women are self-discovered, as they may be 'too young' for traditional screenings like mammograms based on the current industry guidelines." Kratzer said: "As we continue to monitor cancer trends among younger adults, our screening guidelines will adapt to changing risk. However, it is important to understand that there are harms of screening depending on the test, such as overdiagnosis, radiation exposure, and bowel perforation (colorectal cancer). The goal of screening guidelines is to find the best balance between benefits and harms."

How Can Millennial Women Reduce Their Cancer Risk?

Dr. Amy Laughlin, a medical oncologist specializing in breast cancer and cancer genetics at the Orlando Health Cancer Institute, shared her recommendations. "Fat tissue can make hormones, and women who gain weight, especially around menopause, experience higher breast cancer rates. When the ovaries shut off, the contribution of extra weight makes a difference," she told Newsweek. "Exercise is key—around three hours per week is associated with decreased breast cancer recurrence, even in patients who have had breast cancer." Cancer diet recommendations can vary, but the common theme is eating more plant-based and less processed foods. "Eat colorfully—the more colorful the food, the more anticancer properties it has," Laughlin advised. Winer said: "Smoking causes many health problems, so avoid smoking, and given the association of alcohol intake and breast cancer, reducing alcohol intake makes a great deal of sense. "In general, it is recommended that women consume no more than one alcoholic beverage per day," he said. Is there a health issue that's worrying you? Let us know via health@newsweek.com. We can ask experts for advice, and your story could be featured on Newsweek.