Although the rate of colorectal cancer deaths per person has decreased since 1990, the total number of deaths from this cancer linked to low-fiber diets has risen because the global population has grown and aged.

Diets low in fiber, defined as less than 25 grams per day, are linked to approximately 13,145 deaths and 305,676 years of lost healthy life from colorectal cancer globally in 2021, with the greatest impact seen in people over 50 and in low- and middle-income countries.

Colorectal cancer deaths linked to low-fiber diets are highest in middle-income countries and lower in both poorer and wealthier countries, suggesting that economic development and dietary changes interact in complex ways with cancer risk.

In countries where people have shifted from traditional diets to more processed, low-fiber foods, deaths from colorectal cancer have increased sharply—by more than 480% in some places—suggesting that this dietary shift is strongly linked to higher cancer mortality.

Between 1999 and 2020, the number of deaths from colorectal cancer among U.S. adults aged 25 to 44 rose slightly, from 2.1 to 2.6 deaths per 10,000 people, after accounting for changes in age distribution.

Since 2013, the number of new colorectal cancer cases per year has risen by 3% each year among U.S. adults aged 20 to 49, while cases have decreased in older adults.