Abstract
BACKGROUND: The global incidence of early-onset colorectal cancer (EOCRC) is rising. We compared trends in dietary fiber intake, a key modifiable risk factor, and its attributable EOCRC burden among young adults in China versus globally from 1990 to 2021. METHODS: Using data from the GDD and GBD 2021 for adults aged 25-49, we analyzed age-standardized mean fiber intake, summary exposure value (SEV) for low intake, and attributable EOCRC mortality and disability-adjusted life years (DALYs). Trends were quantified using the estimated annual percentage change (EAPC). RESULTS: Between 1990 and 2018, China's mean dietary fiber intake increased dramatically from 5.0 to 23.3 g/day (EAPC 5.73%), substantially outpacing the global increase (EAPC 1.41%). This led to a profound reversal in risk exposure; China's SEV for low fiber declined at nearly twice the global rate (EAPC -2.14% vs -1.15%), falling below the global benchmark after 2005. Consequently, the attributable age-standardized mortality rate in China dropped from 0.15 per 100,000 to converge with the global level of 0.05 by 2021 (EAPC -3.81% vs -2.17% globally). Similar rapid declines occurred for DALYs and were more pronounced in women. Favorable epidemiological changes were the primary driver of this reduction. CONCLUSION: China's success in reducing its EOCRC burden from low dietary fiber highlights nutritional improvement as a potent primary prevention strategy, reinforcing the urgent need to promote fiber-rich diets globally.