The rates of early-onset colorectal cancer (EO-CRC) have been rising by 0.5% to 2.4% annually for three decades, accounting for an estimated 12% of all colorectal cancer diagnosed in the United States in 2020. Enhancing the rigor and comprehensiveness of the epidemiology in terms of the exposures and prognostic biomarkers is essential if we are to modify risk factors and underlying mechanisms, ultimately arresting this unduly trend. This commentary serves to describe the disease trend, postulate underlying risk factors and mechanisms driving disease incidence, and proposes a call to action for cancer epidemiologists to promote increased and timely opportunities to intervene on this trend.