- Researchers say ultra-processed foods raise the risk of colorectal cancer in men, but they did not discover any increased risk for women.
- Experts say ultra-processed foods contain sugars, oils, and fats that can increase colorectal cancer risk.
- In addition, they say, these foods are low in nutrients that can help prevent colorectal cancer.
- They add that national programs that make it easier for people to purchase healthy foods should be implemented.
There has been much discussion in recent years about just how much ultra-processed food can increase a person’s chances of getting cancer.
A study published this week in The BMJ, a weekly medical trade journal published by the British Medical Association, provides new data.
Researchers from Tufts University and Harvard University in Massachusetts reported that men who consumed high rates of ultra-processed foods were at a 29% higher risk for developing colorectal cancer than men who consumed much smaller amounts.
They did not find the same association in women.
Another study published in the BMJ today reported a link between ultra-processed foods and the risk of cardiovascular mortality as well as all-cause mortality.
Colorectal cancer is the third most diagnosed cancer in the United States, according to the American Cancer Society.
Previous studies have linked ultra-processed foods to higher risks of heart health issues as well as inflammatory bowel disease and obesity, but few studies have assessed the association between ultra-processed food intake and colorectal cancer risk.
The latest findings were based on research conducted on more than 46,000 men and nearly 160,000 women from three large studies of U.S. healthcare professionals whose dietary intake was assessed every four years using detailed food frequency questionnaires.
What are processed foods?
Most foods are processed to some degree, but ultra-processed foods are considered the most harmful to your health.
In the new study, these foods were listed as carbonated drinks, sausages, biscuits, candies, instant soups/noodles, sweet/savory packaged snacks, and sugary milk-based and fruit-based drinks.
The researchers noted that these foods often contain high levels of added sugar, fat, and/or salt as well as lacking in vitamins and fiber.
The researchers did not specifically identify the exact mechanism linking ultra-processed foods with the increase in colorectal cancer risk, but the scientists have a few hypotheses.
“Ultra-processed foods are usually high in added sugar, oils/fats, and refined starch, altering gut microbiota composition unfavorably and contributing to increased risk of weight gain and obesity Weight gain and obesity are established risk factors for colorectal cancer,” said Lu Wang, Ph.D., a postdoctoral fellow at the Friedman School of Nutrition Science and Policy at Tufts University and lead author of the study.
“Ultra-processed foods are low in nutrients and bioactive compounds that are beneficial for the prevention of colorectal cancer, such as fiber, calcium, and vitamin D. Ultra-processed foods consist of (most) processed meats, which is an established risk factor for colorectal cancer,” she told Healthline.
Beyond poor nutrition profiles, Wang noted that ultra-processed foods commonly contain food additives such as dietary emulsifiers and artificial sweeteners, some types of which have been suggested to increase the pro-inflammatory potential of the gut microbiome, which may promote colon carcinogenesis.
“We do find that subgroups of ultra-processed foods. including processed meat products like hot dogs, salami, and sausages as well as sugar-sweetened beverages, are particularly correlated with the risk of colorectal cancer,” Wang said.
The study is further evidence of the need for policies that limit ultra-processed foods and instead promote eating unprocessed or minimally-processed foods to improve public health, Wang added.
Healthy food programs
Wang said she would like to see national legislation of some kind that would mandate more healthy, affordable food.
Wang said it is important to make healthy foods available and affordable for everyone to encourage people to replace ultra-processed food with healthier fresh produce.
“We’ve seen programs like ‘produce prescription’ taking place to make healthy foods available and affordable for vulnerable groups,” she said.
Wang added that mandatory front-of-package nutrition labeling is another option, “like the mandatory menu calorie labeling that has been taking place, which would incentive the food industry and food vendors to provide healthier food.”
Another issue she said that is certainly not helping is “the continuing unregulated aggressive marketing of and the large subsidies received by the big corporations that profit from [ultra-processed foods].”
Carlos A. Monteiro, a professor in the Department of Nutrition in the School of Public Health at the University of Sao Paulo in Brazil, co-wrote an editorial on the study, “The trouble with ultra-processed foods,” with Geoffrey Cannon, a senior research fellow at the Center for Epidemiological Studies in Health and Nutrition in the School of Public Health at the University of Sao Paulo.
Monteiro told Healthline that the other significant issue is the unregulated marketing of ultra-processed food and the large subsidies received by the corporations that profit from it.
“Everybody needs food,” he said, “but nobody needs ultra-processed foods.”
