Ultra-processed foods include prepackaged soups, sauces, frozen pizza, ready meals and pleasure foods such as hot dogs, sausages, fries, sodas, store-bought cookies, cakes, candies, donuts, ice cream, and many more.
“Literally hundreds of studies link ultra-processed foods to obesity, cancer, cardiovascular disease and general mortality,” said Marion Nestle, Paulette Goddard professor emeritus of nutrition, food studies and public health at New York University. and author of numerous books on food policy and marketing, including 2015’s “Soda Politics: Taking on Big Soda (and Winning)”.
“These two studies continue consistency: ultraprocessed foods are unequivocally associated with an increased risk of chronic disease,” said Nestlé, who was not involved in either study.
The new study, however, found that all types of ultraprocessed foods played a role to some degree.
“We found that men in the top quintile of ultra-processed food consumption, compared to those in the lowest quintile, had a 29% higher risk of developing colorectal cancer,” said senior co-author Fang Fang. Zhang, cancer epidemiologist and president of the division of nutritional epidemiology and data science at the Friedman School of Nutrition Science and Policy at Tufts University in Boston.
That association remained even after researchers took into account a person’s body mass index or diet quality.
Why didn’t the new study find the same risk of colorectal cancer in women?
“The reasons for such a sex difference are still unknown, but it may involve the different roles that obesity, sex hormones and metabolic hormones play in men versus women,” Zhang said.
“Alternatively, women may have chosen” healthier, “ultra-processed foods, said Dr. Robin Mendelsohn, a gastroenterologist at Memorial Sloan-Kettering Cancer Center in New York City who was not involved in the study.
The study found that eating “higher consumption of ultra-processed dairy products – such as yogurt – was associated with a lower risk of colorectal cancer in women,” Zhang said. “Some ultra-processed foods are healthier, such as whole foods that contain little or no added sugar, and yogurt and dairy products.”
Women had a higher risk of colorectal cancer if they ate more ready-to-eat or reheat dishes such as pizza, she said. However, men were more likely to have a higher risk of bowel cancer if they ate lots of meat, poultry, or seafood-based ready-made products and sugary drinks, Zhang said.
“Americans consume a large percentage of their daily calories from ultra-processed foods: 58% in adults and 67% in children,” he added. “We should consider replacing ultraprocessed foods with unprocessed or minimally processed foods in our diet for cancer prevention and the prevention of obesity and cardiovascular disease.”
A link with premature death
However, when the researchers compared the two types of food to see which one contributed the most, they found that ultra-processed foods were “key to defining mortality risk,” said lead author Marialaura Bonaccio, an epidemiologist at the department. of epidemiology and prevention. at the IRCCS Neurologico Mediterraneo Neuromed in Pozzilli, Italy.
In fact, more than 80 percent of the foods classified by the guidelines followed in the study as nutritionally unhealthy were also ultra-processed, Bonaccio said in a statement.
“This suggests that the increased risk of mortality is not due directly (or exclusively) to the poor nutritional quality of some products, but rather to the fact that these foods are mostly ultra-processed,” Bonaccio added.
Not real foods
Why are ultra-processed foods so bad for us? For one, they are “ready-to-eat or reheat industrial formulations made with ingredients extracted from food or synthesized in the laboratory, with little or no whole food,” Zhang told CNN.
These over-processed foods are often high in added sugar and salt, low in dietary fiber, and high in chemical additives, such as artificial colors, flavors, or stabilizers.
“While some ultraprocessed foods may be considered healthier than others, in general, we recommend stepping completely away from ultra-processed foods and focusing on healthy, unprocessed foods – fruits, vegetables, legumes,” Mendelsohn said.
“There is clearly something about ultra-processed foods that causes people to eat more of it without necessarily wanting to or knowing it.” Nestlé said.
“The effects of ultraprocessed foods are quite clear. The reasons for the effects are not yet known,” Nestlé continued. “It would be nice to know why, but until we find out, it’s best to recommend eating ultra-processed foods in as small a quantity as possible.”