Global, regional, and national burden of colorectal cancer attributable to dietary factors, 1990 to 2021: A global burden of disease study 2021

Dietary patterns associated with colorectal cancer (CRC) are changing globally, yet their relationship with socioeconomic development and cancer burden remains underexplored. We estimated the global, regional, and national burden of CRC attributable to dietary risks from 1990 to 2021 using data from the global burden of disease study (GBD) 2021. We conducted a comparative risk assessment using GBD 2021 estimates to quantify mortality and disability-adjusted life years (DALYs) associated with 6 dietary risk factors: low intake of whole grains, fiber, calcium, and milk, and high intake of red and processed meat. Population-attributable fractions were applied to derive age-standardized mortality and DALY rates, stratified by age, sex, geographic region, and socio-demographic index. In 2021, the global age-standardized mortality and DALY rates of CRC attributable to dietary risks were 4.8 (95% uncertainty interval, 1.6-7.5) and 109.7 (37.7-168.5) per 100,000 population, respectively. Between 1990 and 2021, age-standardized mortality rates remained stable within uncertainty intervals. Central Europe reported the highest burden (mortality, 8.6 [2.2-13.4]; DALY, 192.1 [46.3-303.0]). Low whole grain intake contributed substantially to both mortality (2.1 [0.9-3.3]) and DALY (50.2 [20.4-76.3]), with sex-specific differences observed in the relative contribution of dietary risks. Australasia experienced the greatest reductions, whereas Southern Sub-Saharan Africa and Central Latin America experienced the greatest increases. Higher-socio-demographic index regions exhibited greater burden but also showed more pronounced declines. Dietary risks remain an important and uneven contributor to CRC burden worldwide, highlighting the need for context-specific interventions integrated within regional food and healthcare systems.