Ultra-Processed Foods
The Category That Quietly Took Over Kids' Plates
Evidence grade 3 of 5, Mixed. Read how the Atlas grades evidence.
grade 3 is the honest grade: moderate evidence resting on a strong descriptive base plus one landmark controlled trial, with most hard-outcome causation still observational. The descriptive claim that ultra-processed foods (UPF) supply the majority of children's calories is well documented (Wang 2021 JAMA, about 61 to 67 percent of US youth calories 1999 to 2018; CDC data cited in the 2025 AHA Science Advisory, roughly 62 percent of calories for ages 1 to 18). The one landmark experimental signal is Hall 2019, an NIH metabolic-ward randomized crossover trial in 20 adults in which an ad libitum UPF diet drove about 500 more kcal/day and weight gain versus a nutrient-matched unprocessed diet. Beyond that, evidence is observational: the Lane 2024 BMJ umbrella review of 45 pooled meta-analyses (nearly 10 million people) found consistent associations between higher UPF exposure and all-cause mortality, cardiovascular mortality, and mental disorders, and pediatric systematic reviews (De Amicis 2022; Neri 2022 multi-country) link UPF to obesity and adiposity in children, though results are mixed and some cohorts show no significant association. It does not reach grade 4 because NOVA remains a debated research classification with no regulatory definition, the Hall trial is small, short, and in adults, and confounding by nutrient profile, eating behavior, and social factors is not resolved. Even the AHA 2025 advisory stresses that not all UPF are equal and blanket avoidance is not straightforward, which is why the honest family message is directional: build most of a child's diet from whole and minimally processed foods and reduce sugary drinks and sweet snacks first, guided by a pediatrician or registered dietitian rather than food-shaming.
- FDA
- No regulatory definition; NOVA is a research classification
- WADA
- Not prohibited
Reference only. Not medical advice.
What can go wrong
Higher UPF consumption is associated with obesity and weight-related outcomes in children, and with a range of adult outcomes in large observational reviews, though the evidence base is mostly observational and the category is broad, so associations may partly reflect the nutrient profile, eating behavior, or lifestyle and social factors rather than processing itself. Some studies, including a Greek pediatric analysis, found no significant UPF-obesity association, which underscores the mixed picture. The most defensible message is directional: most of a child's diet is best built from whole and minimally processed foods, with UPF and sugary drinks reduced, rather than any single food being demonized or framed as forbidden. For a child's specific diet, growth concerns, or any worry about eating behavior, families are best guided by a pediatrician or registered dietitian, who can tailor advice without food-shaming.
Ultra-processed foods (UPF) are industrial formulations of refined ingredients, additives, and substances rarely used in home kitchens, grouped as the fourth category of the NOVA system developed in Brazil. They now supply a large share of many children's calories, and the share varies sharply by country: US children moved from about 61 to 67 percent of calories between 1999 and 2018, UK children rise from roughly 47 percent at age two to 59 percent by age seven, while figures sit near 40 percent in Greece and about 25 percent among Brazilian schoolchildren. UPF tend to be calorie-dense, lower in fiber, and engineered to be highly palatable, which is associated with easier overconsumption. The strongest causal signal is a small NIH metabolic-ward trial in which adults ate about 500 more calories a day on a UPF diet matched for nutrients. Larger studies linking UPF to obesity and other outcomes in children are consistent but observational, and the category itself is broad and debated.
Packaged, factory-made foods now supply most of the calories on many children's plates, and the global numbers, and their health links, are striking.
What people take it for
These are the reasons people give for taking it. They are not effects it has been shown to have.
What people get wrong
Often said"Processed" and "ultra-processed" mean the same thing, so all packaged food is equally bad.
ActuallyNOVA distinguishes minimally processed foods, such as bagged spinach or plain yogurt, from ultra-processed industrial formulations. The concern centers on the fourth NOVA group, not all packaging, and even researchers acknowledge the category is broad and its boundaries debated (Monteiro et al.; Britannica NOVA overview).
Often saidA single study proved ultra-processed food makes people overeat, so the case is closed.
ActuallyThe strongest causal evidence is one NIH metabolic-ward trial of 20 adults over two weeks per diet (Hall 2019). It is a real controlled signal of about 500 extra kcal/day, but it is small, short, and in adults. Most other evidence is observational, and its authors and independent experts stress that causation in the wider body of research is not established (Hall 2019; Lane 2024 BMJ; Science Media Centre expert reaction).
Often saidUPF intake is similar everywhere, so country comparisons do not matter.
ActuallyIt varies widely and is verifiable: roughly 61 to 67 percent of US children's calories and up to about 68 percent among UK adolescents, versus near 40 percent in Greece and about 25 percent among Brazilian schoolchildren. The gradient tracks the shift away from traditional diets (Wang 2021 JAMA; Neri 2022; Petridi 2025; de Lacerda 2020).
Who profits, and who pushes back
NOVA-based intake studies
UPF supplies roughly 67% of US children's calories and about 61% for UK 2-to-5-year-olds, versus around 40% in Greece and 25% among Brazilian schoolchildren, a striking global gradient.
Pediatric obesity researchers
Higher ultra-processed food intake is associated with greater weight gain and obesity risk in children, independent of total calories in some analyses.
World Obesity Federation
UPF consumption is highest in children and adolescents, exceeding 50% of calories in several countries, paralleling the global rise in childhood obesity.
Methodological caution
NOVA is a research classification, not a regulatory standard, and "ultra-processed" is broad; much evidence is observational, so the robust message is to favor whole and minimally processed foods rather than to demonize single items.
Where the research comes from
Most of the published research on this comes from one place. 62% of it is from US/UK kids: UPF share. Findings that no unrelated group has reproduced are weaker than the study count makes them look.
| Place | Share of published research |
|---|---|
| US/UK kids: UPF share | 62% |
| Greece | 40% |
Research published from: Global.
How we got here
The concept originated in Brazil, not the US or Europe. Carlos Monteiro and colleagues at the University of Sao Paulo introduced the NOVA classification in 2009 and refined the ultra-processed category in later papers, sorting foods by the extent and purpose of industrial processing rather than by nutrients alone. Through the 2010s NOVA moved into national dietary guidelines, first Brazil's 2014 guide and later others, and into research documenting UPF's growing share of children's diets. In the 2020s the landmark Hall 2019 NIH trial, large umbrella reviews such as Lane 2024, and a 2025 American Heart Association Science Advisory brought UPF into mainstream cardiometabolic guidance while keeping open the debate over whether processing itself or the nutrient profile it drives explains the harm.
The concept originates in Brazil, not the United States or Europe. In 2009, Carlos Monteiro and colleagues at the University of Sao Paulo coined the term ultra-processed foods and built the NOVA classification, which sorts foods by the extent and purpose of industrial processing rather than by nutrients alone. NOVA emerged from Brazilian epidemiology amid rising obesity and diabetes, and its four groups run from unprocessed or minimally processed foods, through processed culinary ingredients and processed foods, to ultra-processed formulations. Through the 2010s the framework spread into national dietary guidelines, first in Brazil and later elsewhere, and into research documenting how large a share of children's diets UPF had come to occupy in high-income countries. In the 2020s, multi-country pediatric studies and large umbrella reviews sharpened both the health associations and the disagreement over whether processing itself, or the nutrient profile and eating behavior it drives, explains the harm.
- 2009Monteiro and colleagues at the University of Sao Paulo coin ultra-processed foods and develop the NOVA classification in Brazil
- 2014Brazil's national dietary guidelines adopt NOVA, advising against ultra-processed foods, the first country to do so
- 2019Hall et al. publish the NIH metabolic-ward crossover RCT in Cell Metabolism, the first controlled causal test showing ~500 more kcal/day on a UPF diet
- 2021Wang et al. report in JAMA that US children's calories from UPF rose from 61 to 67 percent between 1999 and 2018
- 2024Lane et al. publish a BMJ umbrella review across ~9.9 million people linking UPF to over 30 health outcomes, while flagging low evidence quality
- 2024UK Gemini cohort finds toddlers get 47 percent of calories from UPF at ~21 months, rising to 59 percent by age 7
- 2025FDA and USDA issue a joint Request for Information to develop a formal US definition of ultra-processed foods
At a glance
- US children
- ~67% of calories from UPF
- UK ages 2-5
- ~61% of calories
- Greece (kids)
- ~40% of calories
- Brazil schoolchildren
- ~25% of calories
What this entry does not yet cover
What follows is unfinished work on our side, not a finding about Ultra-Processed Foods. A short entry is not a safe entry.
- Cost and market. We have not documented what it sells for or who sells it.
- Supply chain. We have not mapped where it is made.
- Who uses it. We have not documented the user groups.
- What could change. No forward-looking summary yet.
- How it compares. We have not set it against the alternatives.
- Children and teenagers. We have not checked what is known about younger people.
Sources
Ultra-processed diets caused about 500 more kcal/day of ad libitum intake and weight gain versus a nutrient-matched unprocessed diet in a 20-adult NIH inpatient randomized crossover trial, the strongest experimental UPF signal.
Hall KD et al., Cell Metabolism (NIH inpatient randomized controlled trial)
NIH summary: heavily processed foods caused study participants to overeat and gain weight in a controlled inpatient trial.
US youth aged 2 to 19 got a rising share of calories from ultra-processed foods, from about 61 percent in 1999 to about 67 percent in 2018, across 33,795 children analyzed.
Wang L et al., JAMA (nationally representative NHANES trend analysis)
Umbrella review of 45 pooled meta-analyses (~9.9 million participants) found consistent associations between higher UPF exposure and all-cause mortality, cardiovascular mortality, and common mental disorders, while flagging observational limits.
Lane MM et al., BMJ umbrella review of epidemiological meta-analyses
AHA Science Advisory: higher UPF intake is consistently associated with poorer cardiometabolic health, but not all UPF are equal and blanket avoidance is not straightforward; CDC data cited show children aged 1 to 18 get about 62 percent of calories from UPF.
NOVA definition: ultra-processed foods are industrial formulations made mostly from substances extracted from foods plus cosmetic additives, the fourth NOVA group, distinct from minimally processed foods.
Monteiro CA et al., Public Health Nutrition (NOVA definition paper)
Systematic review of observational studies found higher UPF consumption associated with obesity and adiposity parameters among children and adolescents, with mixed strength across cohorts.
De Amicis R et al., European Journal of Nutrition (pediatric systematic review)
Multi-country analysis of nationally representative data from eight countries linked higher UPF consumption to an obesity-associated dietary nutrient profile in children and adolescents.
Neri D et al., Obesity Reviews (eight-country pediatric study)
FAO technical report describes the NOVA classification, diet quality, and the health rationale for grouping foods by degree and purpose of processing.