Colorectal cancer cases and death rates in the United States have been declining since the 1980s, likely due to increased awareness and screening, which typically begins at age 50. However, the number of colorectal cancer cases in young adults – those between the ages of 20 and 49 years – is increasing. Findings from a recent study suggest that consumption of sugar-sweetened beverages increases the risk of early-onset colorectal cancer among young women.

Dietary factors play critical roles in colorectal cancer risk. Consumption of plant-based foods has been shown to decrease colorectal cancer risk. For example, ellagic acid, a bioactive compound present in walnuts and pomegranates, breaks down in the gut to yield urolithins, a class of compounds that exert anti-inflammatory and anti-cancer effects. Conversely, evidence suggests that consumption of red meat increases colorectal cancer risk by 20 to 30 percent.

The participants in the present study included approximately 95,000 women who were part of the Nurses Health Study II, a prospective cohort study comprised of female nurses living in the United States during the period spanning 1991 and 2015. The nurses ranged in age between 25 and 42 years and were cancer-free when they enrolled in the study. Every two years, the women provide information about their demographics, lifestyles, and overall health, including whether they have been diagnosed with colorectal cancer. Every four years, they complete food frequency questionnaires that include questions about their dietary patterns. A subset of approximately 41,000 women provided information about their beverage intake during their teen years.

The authors of study found that 109 of the women in the study group developed early onset colorectal cancer. Women who drank two or more servings of sugar-sweetened beverages per day during adulthood were more than twice as likely to develop early onset colorectal cancer than women who consumed less than one serving per week. This risk was dose-dependent, with a 16 percent higher risk per daily beverage increase. If the women drank sugar-sweetened beverages during their teen years, their risk increased 32 percent for each serving per day increase. Replacing sugar-sweetened beverages with artificially sweetened beverages or milk decreased their risk of early onset colorectal cancer by 17 to 36 percent.

These findings suggest that consuming sugar-sweetened beverages during adolescence and adulthood markedly increases a woman’s risk of developing colorectal cancer. Dietary modifications that include consumption of artificially sweetened beverages or milk appears to reduce risk.

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