Ultra-processed food makes up almost two-thirds of calorie intake of UK adolescents
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
Adolescents consume around two-thirds of their daily calories from ultra-processed foods (UPFs), new research from the Universities of Cambridge and Bristol has found.
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 impactsYanaina Chavez-UgaldePolina TankilevitchPerson holding a cheeseburger
The text in this work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. Images, including our videos, are Copyright ©University of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – on our main website under its Terms and conditions, and on a range of channels including social media that permit your use and sharing of our content under their respective Terms.
Exercising during pregnancy normalises eating behaviors in offspring from obese mice
Previous studies in both humans and animal models have shown that the offspring of mothers living with obesity have a higher risk of developing obesity and type 2 diabetes themselves when they grow up. While this relationship is likely to be the result of a complex relationship between genetics and environment, emerging evidence has implicated that maternal obesity in pregnancy can disrupt the baby’s hypothalamus—the region of the brain responsible for controlling food intake and energy regulation.
In animal models, offspring exposed to overnutrition during key periods of development eat more when they grow up, but little is known about the molecular mechanisms that lead to these changes in eating behavior.
In a study published today in PLOS Biology, researchers from the Institute of Metabolic Science and the MRC Metabolic Diseases Unit at the University of Cambridge found that mice born from obese mothers had higher levels of the microRNA miR-505-5p in their hypothalamus—from as early as the fetal stage into adulthood. The offspring of obese mothers chose to eat more specifically of foods that were high in fat, which is consistent with fat sensing being disrupted in the hypothalamus.
Dr Laura Dearden from the Institute of Metabolic Science, the study’s first author, said: “Our results show that obesity during pregnancy causes changes to the baby's brain that makes them eat more high fat food in adulthood and more likely to develop obesity.”
Senior author Professor Susan Ozanne from the MRC Metabolic Diseases Unit and Institute of Metabolic Science said: “Importantly, we showed that moderate exercise, without weight loss, during pregnancies complicated by obesity prevented the changes to the baby's brain.”
Cell culture experiments showed that miR-505-5p levels can be influenced by exposing hypothalamic neurons to long-chain fatty acids and insulin, which are both high in pregnancies complicated by obesity. The researchers identified miR-505-5p as a regulator of pathways involved in fatty acid uptake and metabolism – high levels of the miRNA make the offspring brain unable to sense when they are eating high fat foods. Several of the genes that miR-505-5p regulates are associated with high body mass index in human genetic studies, showing these same changes in humans can cause obesity.
The study is one of the first to demonstrate the molecular mechanisms linking nutritional exposure in utero to eating behavior.
Dr Dearden added: “While our work was only carried out in mice, it may help us understand why the children of mothers living with obesity are more likely to become obese themselves, with early life exposures, genetics and current environment all being contributing factors.”
Reference
Dearden, L et al. Maternal obesity increases hypothalamic miR-505-5p expression in mouse offspring leading to altered fatty acid sensing and increased intake of high-fat food. PLOS Biology; 4 Jun 2024; DOI: 10.1371/journal.pbio.3002641
Adapted from a press release by PLOS Biology
Maternal obesity in pregnancy changes the eating behaviors of offspring by increasing long-term levels of particular molecules known as microRNAs in the part of the brain that controls appetite – but this can be changed by exercise during pregnancy, a study in obese mice has suggested.
We showed that moderate exercise, without weight loss, during pregnancies complicated by obesity prevented the changes to the baby's brainSusan OzanneEngin_Akyurt (Pixabay)Fast food meal of burger and fries
The text in this work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. Images, including our videos, are Copyright ©University of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – on our main website under its Terms and conditions, and on a range of channels including social media that permit your use and sharing of our content under their respective Terms.