Obesity and alcohol consumption are fueling bowel cancer's rising death toll among young adults, according to a 2023 study published in a leading cancer journal.

The study, published last year in the Annals of Oncology, marks the first time bowel cancer (colorectal cancer) deaths among young people -- Millennials and Gen Xers ages 25-49 -- are predicted to rise in some European countries, and confirms a trend researchers first noted in 2021.

Being overweight or obese -- and related health conditions like hyperglycemia and diabetes -- are the primary factors responsible, Dr. Carlo La Vecchia, professor of medical statistics and epidemiology at the University of Milan, Italy, and lead author on the paper said in a news release on the study.

But "heavier alcohol drinking over time in central and northern Europe and the U.K., and reductions in physical activity," have also contributed, he added.

Alcohol consumption has been linked to early onset bowel cancer, which tends to be more aggressive and lethal, when compared to the kind that's diagnosed in older individuals.

In the U.S., colon cancer diagnoses among adults younger than 50 began increasing in the mid-1990s, with deaths rising a short time later. The increase is seen mainly among white individuals, as opposed to Black or Asian, according to the U.S. National Institutes of Health's National Cancer Institute.

In the late 1990s, colorectal cancer was the fourth-leading cause of cancer deaths in both men and women younger than age 50. Now, it's the leading cause of cancer death among such men and the second leading among such women, according to the American Cancer Society.

Millennials -- those born between 1981 and 1996 -- are at twice the risk of colorectal cancer when compared to Baby Boomers born in 1950, according to a 2017 study published in the Journal of the National Cancer Institute. The same research found that people younger than 55 are almost 60% more likely to be diagnosed with late-stage disease than older adults, making survival a greater challenge.

Aside from obesity, sedentary lifestyle, and heavy alcohol use, other potential drivers proposed by researchers include:

Given these statistics, the U.S. Preventive Services Task Force in 2021 recommended that colorectal cancer screenings begin at age 45, down from age 50. Those with risk factors like inflammatory bowel disease, certain types of polyps, and/or family history may need to be screened sooner.

Experts at Yale Medicine and University of California Davis Health recommend that everyone -- young and older adults alike -- watch for the following symptoms and communicate them to their health care provider: