The study found that UPF consumption was highest among adolescents from deprived backgrounds, those of white ethnicity, and younger adolescents.

UPFs are food items that are manufactured from industrial substances and contain additives such as preservatives, sweeteners, colourings, flavourings, and emulsifiers. UPFs vary greatly, but tend to indicate poor dietary quality, with higher levels of added sugars, saturated fat, and sodium, as well as decreased fibre, protein, and micronutrient content. They have been suggested as one of the key drivers of the global rise in diseases such as obesity, type 2 diabetes, and cancer.

Globally, the availability and sales of UPFs have increased over time and previous evidence suggests that this has led to increased consumption among adolescents. To look at trends within the UK, researchers from Cambridge and Bristol analysed data from four-day food diaries of almost 3,000 adolescents in the UK National Diet and Nutrition Survey between 2008/09 and 2018/19.

In research published today in the European Journal of Nutrition, the researchers found that a mean of 66% of adolescents’ energy intake came from UPF consumption during this period, though there was a slight fall from 68% to 63% between 2008/09 and 2018/2019.

Parents’ occupation, ethnic group and UK region all influenced the proportion of calorie intake from UPFs:

• Adolescents from disadvantaged backgrounds consumed a higher proportion of their calorie intake from UPFs compared to adolescents from less disadvantaged backgrounds (68.4% compared with 63.8%).
• Adolescents from a non-white ethnicity consumed a lower proportion of their calorie intake from UPFs (59.0% compared with 67.3%).
• Adolescents living in the North of England consumed a higher proportion of their calorie intake from UPFs compared with those living in the South of England and London (67.4% compared with 64.1%).
• 18-year-olds consumed a lower proportion of their calorie intake from UPFs compared with 11-year-olds (63.4% compared with 65.6%).

Dr Yanaina Chavez-Ugalde from the Medical Research Council (MRC) Epidemiology Unit at the University of Cambridge, the study’s first author, said: “Adolescents’ food patterns and practices are influenced by many factors, including their home environment, the marketing they are exposed to and the influence of their friends and peers. But adolescence is also an important time in our lives where behaviours begin to become ingrained.

“It’s clear from our findings that ultra-processed foods make up the majority of adolescents’ diets, and their consumption is at a much higher level than is ideal, given their potential negative health impacts.”

The researchers argue that the observed reduction in UPF intake pre-pandemic could be partly explained by an increased public awareness and health concerns associated with sugar consumption, government-led campaigns, sugar-taxes in other countries and the reformulation of sugary drinks to reduce their sugar content.

Dr Esther van Sluijs from the MRC Epidemiology Unit at Cambridge, joint senior author, said: “Ultra-processed foods offer convenient and often cheaper solutions to time- and income-poor families, but unfortunately many of these foods also offer poor nutritional value. This could be contributing to the inequalities in health we see emerging across childhood and adolescence.”

Dr Zoi Toumpakari from the Centre for Exercise, Nutrition and Health Sciences at the University of Bristol, joint senior author, added: “Our findings suggest that disparities in consumption of ultra-processed foods are not just down to individual choices. We hope this evidence can help guide policymakers in designing more effective policies to combat the negative effects of ultra-processed food consumption among youth and the ripple effects this has on public health.”

This study was largely funded by the National Institute for Health and Care Research School for Public Health Research.

Reference
Chavez-Ugalde, Y et al. Ultra-processed food consumption in UK adolescents: distribution, trends, and sociodemographic correlates using the National Diet and Nutrition Survey 2008/09 to 2018/19. Eur J Nutr; 17 Jul 2024; DOI: 10.1007/s00394-024-03458-z

Comparing two menus reflecting a typical Western diet — one emphasizing minimally processed foods and the other emphasizing ultra-processed foods, as categorized by the NOVA classification system — the researchers found that the less processed menu was more than twice as expensive and reached its expiration date over three times faster without delivering any additional nutritional value.

“This study indicates that it is possible to eat a low-quality diet even when choosing mostly minimally processed foods,” said Julie Hess, PhD, a research nutritionist at the USDA-ARS Grand Forks Human Nutrition Research Center, who led the study. “It also shows that more-processed and less-processed diets can be equally nutritious (or non-nutritious), but the more-processed diet may have a longer shelf life and be less costly.”

Mark Messina, PhD, director of nutrition science and research at Soy Nutrition Institute Global, will present the findings at NUTRITION 2024, the flagship annual meeting of the American Society for Nutrition held June 29–July 2 in Chicago.

The new research builds on a study the team published last year, which demonstrated that it was possible to build a high-quality menu that aligns with dietary guidelines while deriving most of its calories from foods classified as ultra-processed. For the new study, the researchers asked the opposite question: Is it possible to build a low-quality menu that derives most of its calories from “simple” foods?

To find out, they constructed a less-processed menu, which derived 20% of its calories from ultra-processed foods, and a more-processed menu, which derived 67% of its calories from ultra-processed foods. The level of processing involved in each menu was determined according to the NOVA system of classification.

The two menus were calculated to have a Healthy Eating Index score of about 43-44 out of 100, a relatively low score that reflects poor adherence to the Dietary Guidelines for Americans. The researchers estimated that the less-processed menu would cost $34.87 per day per person compared with $13.53 per day for the more-processed menu. They also calculated that the median time to expiration of the less-processed menu items was 35 days versus 120 days for the more-processed menu items.

The study draws attention to the disconnects between food processing and nutritional value. Hess noted that some nutrient-dense packaged foods can be classified as ultra-processed, such as unsweetened applesauce, ultrafiltered milk, liquid egg whites and some brands of raisins and canned tomatoes.

“The results of this study indicate that building a nutritious diet involves more than a consideration of food processing as defined by NOVA,” said Hess. “The concepts of ‘ultra-processed’ foods and ‘less-processed’ foods need to be better characterized by the nutrition research community.”

Messina will present this research at 12:45-1:45 p.m. CDT on Sunday, June 30, during the Food Choice, Markets and Policy poster session in McCormick Place (abstract; presentation details).

Please note that abstracts presented at NUTRITION 2024 were evaluated and selected by a committee of experts but have not generally undergone the same peer review process required for publication in a scientific journal. As such, the findings presented should be considered preliminary until a peer-reviewed publication is available.

Find more news briefs from NUTRITION 2024 at: https://www.eurekalert.org/newsroom/nutrition2024/home.

“Higher intake of ultra-processed food was positively associated with risk of IBD. Further studies are needed to identify the contributory factors within ultra-processed foods,” the authors said.

Ultra-processed foods include packaged baked goods and snacks, fizzy drinks, sugary cereals, ready meals containing food additives, and reconstituted meat and fish products.

These products also often contain high levels of added sugar, fat and salt, but lack vitamins and fiber.

The researchers analyzed detailed dietary information from 116,087 adults aged 35-70 years living in 21 low, middle and high income countries who enrolled in the Prospective Urban Rural Epidemiology (PURE) study.

Subjects enrolled in PURE between 2003 and 2016, and they were evaluated least every three years.

The average follow-up was 9.7 years. During follow-up the researchers recorded new diagnoses of IBD, including Crohn’s disease or ulcerative colitis.

During follow-up, 467 subjects developed IBD, 90 with Crohn’s disease and 377 with ulcerative colitis.

After adjusting for other factors, the researchers reported that higher intake of ultra-processed food was associated with a higher risk of IBD.

Compared to those who consumed less than one serving of ultra-processed food per day, there was an 82% increased risk of IBD among those who consumed five or more servings per day, and a 67% increased risk for 1-4 servings per day.

Various subgroups of ultra-processed food, including soft drinks, refined sweetened foods, salty snacks, and processed meat, each were associated with higher risks of development of  IBD.

Notably, white meat, red meat, dairy, starch, and fruit, vegetables and legumes were not associated with development of IBD.

While this is an observational study so can’t establish causality, the investigators said the findings “support the hypothesis that intake of ultra-processed foods could be an environmental factor that increases the risk of IBD.”