Why is colorectal cancer mortality increasing in young adults in the US?

We’ve found that colorectal cancer deaths have been rising by about 1% each year since 2004 among people under 50 in the U.S., even as rates have fallen in older adults [1]. This pattern suggests a growing trend of younger people being diagnosed and dying from this disease, though we don’t yet know why. The evidence we’ve reviewed so far does not explain the cause — only that the increase is happening. We have not seen any studies that contradict this observation. What we’ve found so far leans toward a real and ongoing shift in who is affected, but we cannot say what factors — like diet, lifestyle, environment, or screening habits — might be driving it. Our current analysis shows this trend is clear in the data, but the reasons behind it remain unclear. We don’t have enough evidence to link it to any one behavior, exposure, or medical factor. For now, the pattern itself is the only consistent finding. If you’re under 50 and notice changes in bowel habits, unexplained weight loss, or persistent fatigue, it’s worth talking to a doctor — not because you’re likely to have colorectal cancer, but because early detection can make a difference when it does occur.