Sugary drinks linked to increased risk of early-onset colorectal cancer in young women

CANCER DIGEST – May 8, 2021 – Young women who drank two or more servings per day had just over twice the risk of being diagnosed with colorectal cancer before age 50 than those who drank much less, a new study finds.

The study led by Yin Cao, ScD, an associate professor of surgery and of medicine in the Division of Public Health Sciences at Washington University analyzed data from 41,000 participants in the Nurses' Health Study II, a large population study tracked the health of nearly 116,500 female nurses from 1991 to 2015. The study appears in the May 6 journal Gut.

"Colorectal cancer in younger adults remains relatively rare, but the fact that the rates have been increasing over the past three decades – and we don't understand why – is a major public health concern and a priority in cancer prevention," said senior author Cao in a press release. "Due to the increase in colorectal cancer at younger ages, the average age of colorectal cancer diagnosis has gone down from 72 years to 66 years. These cancers are more advanced at diagnosis and have different characteristics compared with cancers from older populations."

Sugar-sweetened drink consumption has been linked to metabolic health problems, such as type 2 diabetes and obesity, including in children. But less is known about whether such high-sugar beverages could have a role in the increasing incidence of colorectal cancer in younger people.

To find out, the researchers surveyed 95,000 participants in the Nurses Study about diet every four years. A subset of 41,000 of these participants also reported the types and estimated amounts of beverages they drank at age 13–18 years. Compared with women who consumed less than 1 serving of sugared soda beverages per week in adulthood, women who consumed more than 2 servings per day had more than twice the risk of early-onset colorectal cancer.

They also found that replacing each serving per day of adulthood sugared drinks with that of artificially sweetened beverages, coffee, reduced fat milk or total milk was associated with a 17%–36% lower risk of early-onset colorectal cancer.

While this observational study cannot link cancer to sugary beverage, the researchers think it is significant to recommend reducing consumption of such drinks.

"Given this data, we recommend that people avoid sugar-sweetened beverages and instead choose drinks like milk and coffee without sweeteners," Cao said.

Sources: Washington School of Medicine press release and the journal Gut