Global, country, and regional cancer burden attributable to dietary risk: Results from the global burden of disease study 2021.

Background: The distribution of diet-attributable cancer burden has not been systematically analyzed globally. This study aimed to analyze the diet-attributable cancer burden using the Global Burden of Disease (GBD) database to provide insights into reducing the dietary risk-related cancer burden across regions with different development levels.

Methods: Data on cancer deaths and disability-adjusted life years (DALYs) attributable to diet were downloaded from the GBD database (1990-2021). The cancer burden attributable to nine dietary factors and total dietary factors was sorted, and Joinpoint regression analysis was performed according to the Socio-Demographic Index (SDI) regions. Then, using the DALYs data, a health inequality analysis was conducted, and the Slope Index of Inequality (SII) and concentration indices (CI) for 1990 and 2021 were calculated.

Results: From 1990 to 2021, the global cancer burden attributed to diet decreased continuously, with an average annual percentage change (AAPC) of -1.40 (-1.48, -1.32) for mortality (P < 0.01) and an AAPC of -1.49 (-1.57, -1.42) for DALYs (P < 0.01). Colon and rectal cancers were the most influenced by dietary factors, with diet-attributable deaths comprising 71.70% and 68.14% of total deaths in 1990 and 2021, respectively, followed by breast and stomach cancers, which both exceeded 40% in both years. The diet-related cancer burden decreased rapidly in the high and high-middle SDI regions with AAPCs for both mortality and DALYs being less than 0 (P < 0.01). In contrast, there was Little improvement in the low- and low-middle SDI regions. In 2021, the absolute values of the SII (296.72) and CI (-0.17) attributed to global dietary risks were higher than those in 1990 with the SII of 267.61 and CI of -0.17.

Conclusion: Dietary factors continued to be a significant risk factor for cancer in 2021. High red meat consumption, low intake of whole grains, and low milk intake were the three primary dietary risks.