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Children and teens in the United States now get more than two-thirds of their calories from ultra-processed foods, according to an analysis of nearly two decades of data.
Ultra-processed foods, such as frozen pizza, microwavable meals, packaged snacks and desserts, accounted for 67% of calories consumed in 2018, up from 61% in 1999, according to research published Tuesday in the medical journal JAMA. The study analyzed the diet of 33,795 children and adolescents nationwide.
While industrial processing can keep foods fresher longer and allow some to be fortified with vitamins, it modifies foods to change their consistency, flavor and color to make them tastier, cheaper and more convenient, using processes not used in foods. cooked at home. foods. They are also aggressively marketed by the food industry.
“Some whole-grain breads and dairy products are ultra-processed and are healthier than other ultra-processed foods,” said lead author Fang Fang Zhang, a nutrition and cancer epidemiologist at the Friedman School of Nutrition Science and Policy at Tufts University. in Boston.
“But many ultra-processed foods are less healthy, with more sugar and salt, and less fiber, than unprocessed and minimally processed foods, and the increase in their consumption by children and adolescents is worrying.”
Information on children’s diets used in the study was collected annually by trained interviewers who asked the children or an adult acting on their behalf to detail what they had eaten in the previous 24 hours. The information was collected as part of the National Health and Nutrition Examination Survey.
Between 1999 and 2018, the proportion of healthier foods, unprocessed or minimally processed, decreased from 28.8% to 23.5% of calories consumed, the study found.
The remaining percentage of calories came from moderately processed foods, such as cheese and canned fruits and vegetables, and flavor enhancers such as sugar, honey, maple syrup and butter, according to the study.
The biggest increase in calories came from ready-to-eat or ready-to-heat meals, such as takeout and frozen pizzas and burgers: from 2.2% to 11.2% of calories, according to the study. The second largest increase came from packaged sweet snacks and desserts, whose consumption increased from 10.6% to 12.9%.
The link between childhood health and ultra-processed foods is complex, but a recent study in the United Kingdom found that children who eat more ultra-processed foods are more likely to be overweight or obese in adulthood.
Experts said the study’s implications for future health were significant given that childhood is a critical period for biological development and the formation of eating habits.
“The current food system is structured to promote the overconsumption of ultra-processed foods through a variety of strategies, including pricing and promotions, aggressive marketing, including targeting youth and specifically Black and Latino youth, and a high availability of these products in schools,” wrote Katie Meyer and Lindsey Smith Taillie, both assistant professors in the department of nutrition at the University of North Carolina Gillings School of Global Public Health, in a commentary on the study. They did not participate in the investigation.
There was good news suggesting that efforts to address sugary drink consumption, such as soda taxes, had been effective: calories from sugary drinks fell from 10.8% to 5.3% of total calories.
“We need to mobilize the same energy and level of commitment when it comes to other unhealthy ultra-processed foods like cakes, cookies, donuts and brownies,” Zhang said.
Non-Hispanic black youth experienced a greater increase in the proportion of ultra-processed foods in their diet compared to their white counterparts. The study said it did not evaluate trends in other racial or ethnic groups due to a lack of nationally representative data. However, he noted that Mexican-American youth consume ultra-processed foods at a consistently lower rate, which the authors said could reflect greater home cooking among Hispanic families.
Parents’ educational level or family income had no impact on the consumption of ultra-processed foods, suggesting that they are common in the diet of most children, the study added.
The authors said their study had some limitations: Asking people to remember what they ate is not always an accurate measure of dietary intake. Furthermore, there is a tendency to underestimate socially undesirable habits, such as the consumption of unhealthy foods.
Additionally, it can be challenging to accurately classify ultra-processed foods because it requires a complete list of ingredients, information that children answering a questionnaire are unlikely to provide.
“Better methods of dietary assessment and food classification are needed to understand the trends and mechanisms of action of ultra-processed food intake,” Mayer and Taillie wrote.
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