Early-Onset Disease

Colorectal cancer (bowel cancer) is one of the most common cancers worldwide. While it has traditionally affected older adults, cases in younger people under 50 (called early-onset colorectal cancer (EOCRC)) are rising quickly.

This increase has been seen in the UK and across the world. Younger patients are also often diagnosed at later stages because routine screening usually starts later in life. That means the disease can be more aggressive and harder to treat.

Research suggests that EOCRC may be linked to lifestyle and environmental factors such as diet, obesity, physical inactivity, alcohol, and smoking. This is alongside changes in the gut microbiome (the community of bacteria in our digestive system). Certain bacteria and their by-products can either damage DNA and promote cancer, or help protect against it, depending on diet and other exposures.

Some protective factors for EOCRC include having a Mediterranean-style diet, high fiber and calcium intake.

Because most studies so far have focused on older adults, we still know little about why younger people are increasingly affected.