Eating ultra-processed foods may lead to an increased risk of precancerous polyps for women under 50, according to a study published Thursday in JAMA Oncology.
The study of 29,105 female nurses younger than 50 found that women who had an average of three ultra-processed food servings per day had a 3% risk of a precancerous polyp.
Women who had an average of 10 or more ultra-processed food servings per day had a 5% risk.
Study participants who reported consuming the highest levels of ultra-processed foods had a 45% higher risk of developing adenomas.
Examples of ultra-processed foods include sodas, prepackaged snacks — such as chips, cookies and crackers — candy, boxed macaroni and cheese, frozen and ready-to-eat meals, lunch meats, jerky and hot dogs.
The study, conducted from 1991 to 2015 and led by Harvard and Mass General Brigham researchers, could not directly prove that eating the foods caused the growths, however.
The women received at least two lower endoscopies before they turned 50 to screen for colorectal cancer precursors and also completed dietary surveys every four years for researchers to estimate their daily average intake of ultra processed foods.
“Our findings support the importance of reducing the intake of ultra-processed foods as a strategy to mitigate the rising burden of early-onset colorectal cancer,” said senior author Andrew Chan, a gastroenterologist at the Mass General Brigham Cancer Institute and a professor at Harvard Medical School.
“The increased risk seems to be fairly linear, meaning that the more ultra-processed foods you eat, the more potential that it could lead to colon polyps.”
The researchers had “detailed information about other colorectal cancer risk factors in the participants, such as body mass index, Type 2 diabetes, and low fiber intake,” said Chan.
“Even after accounting for all these other risk factors, the association with ultra-processed foods still held up.”
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