Are ultra-processed foods a public health hazard?
Yes — a growing scientific and policy consensus says UPFs are a public health hazard, though important nuances remain
The core evidence
A major three-paper series published in The Lancet in late 2025 represents the most comprehensive assessment to date. The researchers concluded that "this pattern increases the risk of multiple diet-related chronic diseases through various mechanisms—is substantiated by more than 100 prospective studies, meta-analyses, randomised controlled trials, and mechanistic studies, covering adverse outcomes across nearly all organ systems." As Professor Barry Popkin put it, "We can say now that truly ultraprocessed food represents a clear global threat to our health - not only our physical health but also mental health in terms of its impacts on depression."
A 2024 umbrella review in The BMJ found "consistent evidence shows that higher exposure to ultra-processed foods is associated with an increased risk of 32 damaging health outcomes including cancer, major heart and lung conditions, mental health disorders, and early death."
Specific disease links include:
Why UPFs may be harmful — beyond just "junk food"
Researchers argue processing itself matters, not just nutrient content. A randomized controlled NIH trial found that when people were given a high-UPF diet they ate more calories and gained significantly more weight than when given a minimally processed diet, even though both diets contained the same nutrients. Possible mechanisms include inflammation, immune system dysregulation, and changes in the gut microbiome. The Johns Hopkins Bloomberg School notes that processing affects how bodies metabolize food, making it "pre-digested," leading to rapid absorption of sugar and fat, spikes in blood glucose, and disruption of the gut microbiome from low fiber and additives like emulsifiers—over time increasing risk of inflammatory bowel disease and insulin resistance.
Scale of exposure
This isn't a marginal issue — UPFs dominate modern diets. In the U.S., the overall mean percentage of total calories from ultra-processed foods was 55.0% among people age 1+, with youth consuming a higher share (61.9%) than adults (53.0%).
Important caveats and nuance
Not everyone agrees the category is precise enough to drive policy. One critic warned: "By focusing on a - such an imprecise target as ultraprocessed foods, there's a risk of demonizing perfectly healthy foods, giving a health halo to patently unhealthy foods and opening the door for industry manipulation."
The American Heart Association's 2025 science advisory echoes this: not all UPFs are junk foods or have poor nutritional quality; some UPFs have better nutritional value and can be part of an overall healthy dietary pattern. Research has found that ultra-processed whole grain breads and cereals were associated with neither positive nor negative impacts on health, and ultra-processed vegetables and legumes were associated with a reduced likelihood of death.
Most of the underlying evidence is also observational rather than experimental. As the NHLBI notes, while observational studies linking UPFs to cardiovascular disease are growing, rigorous clinical trials—the gold standard of scientific research—are largely lacking.
The policy response
The strength of evidence has triggered real-world action. France's Mathilde Touvier stated: "While healthy debate about UPFs within the scientific community is welcomed, this should be distinguished from attempts by vested interests to undermine the current evidence. The growing body of research suggests diets high in ultra-processed foods are harming health globally and justifies the need for policy action."
In the U.S., federal agencies have taken notice: under HHS Secretary Robert F. Kennedy Jr. and USDA Secretary Brooke Rollins, the FDA and USDA announced a joint Request for Information to help establish a federally recognized uniform definition for ultra-processed foods. California has gone further, becoming the first U.S. state to enact a law to define and ban unhealthy ultra-processed foods from meals served to schoolchildren starting in the 2025–2026 school year. Lancet authors have called for a playbook similar to what was used against Big Tobacco, including taxes on sodas, warning labels on packaged foods, bans on marketing to kids, and removing UPFs from institutions like schools and hospitals.
Bottom line
The weight of evidence—spanning hundreds of observational studies, several meta-analyses, mechanistic research, and at least one rigorous controlled feeding trial—supports treating high UPF consumption as a genuine public health concern linked to obesity, diabetes, cardiovascular disease, certain cancers, depression, and premature death. However, scientists caution against treating the UPF category as monolithic: the health harm appears concentrated in specific types (sugary drinks, processed meats, salty snacks) rather than all industrially processed foods equally, and more randomized trials are needed to establish causation and identify which mechanisms or specific foods matter most.
Citations (19)
- Ultra-processed foods and human health: the main thesis and the evidence - The Lancet
Source excerpt: “The third and final hypothesis—that this pattern increases the risk of multiple diet-related chronic diseases through various mechanisms—is substantia...”
evidence, article, points to yes. Claim: Lancet series concluded UPF patterns raise risk of multiple chronic diseases, substantiated by over 100 studies across nearly all organ systems.
- Ultra-processed foods are a threat to public health, scientists say : NPR
Source excerpt: “BARRY POPKIN: We can say now that truly ultraprocessed food represents a clear global threat to our health - not only our physical health but also men...”
attribution, article, points to yes. Claim: Barry Popkin says ultraprocessed food is a clear global threat to physical and mental health.
- Consistent evidence links ultra-processed food to over 30 damaging health outcomes - BMJ Group
Source excerpt: “Findings underscore need for urgent research to understand how ultra-processed foods affect health and measures to target and reduce exposure Consiste...”
evidence, article, points to yes. Claim: BMJ umbrella review found consistent evidence linking higher UPF exposure to 32 damaging health outcomes.
- Excessive ultraprocessed foods (UPFs) and poor nutrition tied to poor health | American Heart Association
Source excerpt: “... A meta-analysis of prospective studies cited in the advisory found a dose-response relationship between UPF consumption and cardiovascular events,...”
statistic, article, points to yes. Claim: Meta-analysis found dose-response relationship between UPF consumption and cardiovascular events, with higher cardiometabolic and mortality risk.
- Ultra-processed Foods and Your Health Risks | Tufts Solutions
Source excerpt: “Researchers at the Friedman School of Nutrition Science and Policy found that for every 10% increase in calories from ultra-processed foods, mortality...”
statistic, article, points to yes. Claim: Tufts research: each 10% increase in calories from UPFs raised mortality risk by 9%.
- Ultra-Processed Foods May Be Associated With Adverse Health Outcomes - American College of Cardiology
Source excerpt: “Each additional 100 g/day of ultra-processed food consumption was associated with a 14.5% higher risk of hypertension, 5.9% increased risk of cardiova...”
statistic, article, points to yes. Claim: Each additional 100 g/day of UPF linked to higher hypertension, cardiovascular, cancer, digestive disease and mortality risk.
- Global surge in ultra-processed foods sparks urgent health warning | ScienceDaily
Source excerpt: “Eating Ultra Processed Foods May Speed Up Early Signs of Parkinson's Disease · May 7, 2025 People who eat more ultra processed foods like cold break...”
evidence, article, points to yes. Claim: UPF consumption linked to early signs of Parkinson's disease and cognitive decline.
- Spotlight on UPFs: NIH explores link between ultra-processed foods and heart disease | NHLBI, NIH
Source excerpt: “An exception is a small NIH-supported clinical trial conducted in 2019 that linked UPFs to obesity, a risk factor for heart disease. The study found t...”
evidence, article, points to yes. Claim: NIH trial found high-UPF diet led to more calories eaten and greater weight gain than minimally processed diet.
- Spotlight on UPFs: NIH explores link between ultra-processed foods and heart disease | NHLBI, NIH
Source excerpt: “· Other possible mechanisms that may explain how UPFs are linked to heart disease are independent of calorie consumption, Hall said. They include infl...”
evidence, article, points to yes. Claim: Possible mechanisms include inflammation, immune dysregulation and gut microbiome changes, independent of calorie intake.
- What Are Ultra-Processed Foods? | Johns Hopkins | Bloomberg School of Public Health
Source excerpt: “The disassembling and reassembling of chemical and physical structures caused by processing affects how our bodies metabolize these foods, making them...”
evidence, article, points to yes. Claim: Processing makes food pre-digested, causing rapid absorption, glucose spikes and microbiome disruption, raising IBD and insulin resistance risk.
- Products - Data Briefs - Number 536 - August 2025
Source excerpt: “Keywords: Nova, caloric intake, National Health and Nutrition Examination Survey (NHANES) The overall mean percentage of total calories consumed from ...”
statistic, official document, points to yes. Claim: US mean share of calories from UPFs is 55.0%, higher in youth (61.9%) than adults (53.0%).
- Ultra-processed foods are a threat to public health, scientists say : NPR
Source excerpt: “DAVID LUDWIG: By focusing on a - such an imprecise target as ultraprocessed foods, there's a risk of demonizing perfectly healthy foods, giving a heal...”
attribution, article, points to no. Claim: David Ludwig warns the UPF category is imprecise, risking demonizing healthy foods and enabling industry manipulation.
- Excessive ultraprocessed foods (UPFs) and poor nutrition tied to poor health | American Heart Association
Source excerpt: “However, not all UPFs are junk foods or have poor nutritional quality; some UPFs have better nutritional value and can be part of an overall healthy d...”
evidence, article, points to no. Claim: AHA advisory says not all UPFs are junk foods; some can be part of a healthy diet.
- Ultra-processed Foods and Your Health Risks | Tufts Solutions
Source excerpt: “The exceptions were ultra-processed whole grain breads and cereals, which were associated with neither positive nor negative impacts on health, and ul...”
evidence, article, points to no. Claim: Ultra-processed whole grain breads and cereals showed neither positive nor negative health impacts; some UPF vegetables and legumes linked to lower mortality.
- Spotlight on UPFs: NIH explores link between ultra-processed foods and heart disease | NHLBI, NIH
Source excerpt: “While observational studies linking UPFs to cardiovascular disease are growing, rigorous clinical trials – the gold standard of scientific research – ...”
evidence, article, points to no. Claim: Observational UPF-cardiovascular studies are growing but rigorous clinical trials are largely lacking.
- Global surge in ultra-processed foods sparks urgent health warning | ScienceDaily
Source excerpt: “Professor Mathilde Touvier, French National Institute for Health and Medical Research (Inserm), France, states, "While healthy debate about UPFs withi...”
attribution, article, points to yes. Claim: Mathilde Touvier says evidence shows UPF-heavy diets harm health globally and justifies policy action.
- HHS, FDA and USDA Address the Health Risks of Ultra-Processed Foods | USDA
Source excerpt: “(Washington, D.C., July 23, 2025) – Under the leadership of the U.S. Department of Health and Human Services Secretary Robert F. Kennedy, Jr. and the ...”
evidence, official document, points to yes. Claim: FDA and USDA announced a joint Request for Information to establish a federal definition of ultra-processed foods.
- What Are Ultra-Processed Foods? | Johns Hopkins | Bloomberg School of Public Health
Source excerpt: “In June, California voted to enact the first U.S. law to define and ban unhealthy ultra-processed foods from an estimated over 1 billion meals served ...”
evidence, article, points to yes. Claim: California became first state to enact a law defining and banning unhealthy UPFs from school meals.
- Ultra-processed foods are a threat to public health, scientists say : NPR
Source excerpt: “GODOY: Yeah, they say it's time to use a playbook similar to what was used against Big Tobacco, so things like taxes on sodas, warning labels on packa...”
attribution, article, points to yes. Claim: Lancet authors call for a Big Tobacco-style playbook: soda taxes, warning labels, marketing bans, removal from schools and hospitals.