A higher intake of sugar-sweetened beverages (SSBs) in adulthood and adolescence was linked to an increased risk of early-onset colorectal cancer (CRC) in women, according to data from a large prospective study.
The Nurses’ Health Study II followed over 95 000 registered nurses from 1991 to 2015. Those consuming at least two SSB servings a day in adulthood had more than double the early-onset CRC risk of those consuming less than one serving a week. This rose by 16% with each extra serving per day.
In the adolescent years of ages 13 to 18, each serving-per-day increment was associated with a 32% higher risk of early-onset CRC. Meanwhile, replacing each SSB serving per day for adults with a serving of a non-SSB drink was associated with a 17-36% lower risk.
“Considering the well-established, adverse health consequences of SSBs and the highest consumption being characterized in adolescents and young adults under age 50 years, our findings reinforce the public health importance of limiting SSB intake for better health outcomes,” Yin Cao, ScD, MPH, of Washington University in St. Louis, and co-researchers wrote.
Although CRC has been on the decline, the age of early onset — that is, diagnosed before age 50 — has been increasing the past two decades. In comparison to adults born around 1950, those born around 1990 had twice the colon cancer risk and four times the rectal cancer risk.
An estimated 12% of the US population currently consume more than three SSB servings per day, as shown by National Health and Nutrition Examination Survey data. SSBs in the US are often include high fructose corn syrup as an ingredient, as opposed to South Africa which uses cane sugar.
In this study, the population consisted overwhelmingly of white females, ages 25 to 42, with an average age of approximately 42 at enrollment. Over up to 24-plus years of follow-up, 109 cases of early-onset CRC were recorded.
The researchers found that those with higher SSB intakes in adulthood tended to be less physically active and more likely to have a lower endoscopy history, to use non-steroidal anti-inflammatory drugs, and consume red and processed meats. They were also less likely to take multivitamins and to have a reduced intake of alcohol, fibre, folate, and calcium, and to have a poorer diet overall.
No association was found between intake of artificially sweetened beverages or fruit juice in adulthood and risk of early-onset CRC, mirroring past research.
The investigators listed a number of possible pathways for the effect of SSBs on early-onset CRC.
For example, compared with isocaloric solid foods, energy-containing beverages do not create a feeling of satiation, leading to weight gain. SSBs also initiate rapid blood glucose response and insulin secretion, possibly leading to insulin resistance, inflammation, obesity, and type 2 diabetes — metabolic conditions which are linked to heightened CRC risk.
Other possibilities include intestinal dysbiosis and endotoxemia caused by high fructose levels , the principal sweetener in SSBs in the US and certain other countries, which can impair gut barrier function, increasing gut permeability, and possibly promote cancer formation. A recent experimental study suggested that the high-fructose corn syrup in SSBs from the US enhanced the growth of aggressive tumours in mice, regardless of weight and metabolic syndrome.
High-fructose corn syrup has also been linked to metabolic dysregulation, regardless of obesity.
Fortunately, overall SSB intake has been trending downward in recent years, and Dr Cao and co-authors concluded that further limiting consumption may be “an actionable strategy to curb the rising incidence of [early-onset] CRC.”
Study limitations, the researchers said, included possible unknown confounding variables, the few early-onset CRC cases prevented pinpointing the window of exposure, and there weren’t enough diabetic participants to stratify by a personal history of diabetes. Since the participants were mostly white women, the results were not readily generalisable to other ethnic groups or to men.
Source: MedPage Today
Source Reference: Hur J, et al “Sugar-sweetened beverage intake in adulthood and adolescence and risk of early-onset colorectal cancer among women” Gut 2021; DOI: 10.1136/gutjnl-2020-323450.
