Are ultra-processed foods a public health hazard?

Ultra-processed foods and public health risk — I'll pull the evidence for your answer.

Yes - the scientific consensus has shifted rapidly in the last 2-3 years toward viewing diets high in ultra-processed foods (UPFs) as a major public health hazard, comparable in policy framing to tobacco.

1. What counts as ultra-processed?

Most research uses the NOVA classification, developed by researchers at the University of São Paulo led by Carlos Monteiro. It sorts foods by degree of industrial processing rather than nutrients:

The system is accepted today by international organizations such as FAO or WHO.

UPFs are defined in recent literature as branded products made from cheap, food-derived substances and additives, designed and marketed to displace real food (Nova groups 1-3) and freshly prepared meals, while maximising industry profits. Typically, they contain a range of additives, are energy-dense and high in sugar and salt, but low in dietary fibre, protein, vitamins, and minerals.

Global exposure is high. In the United States, 55% of calories consumed come from ultra-processed foods. For children and teens, that number jumps to nearly 62%. From 2007 to 2022, total UPF sales increased in low-income and middle-income countries, but remained stable in high-income countries, where consumption is already entrenched.

The World Health Organization (WHO) is working to develop evidence-based global guidance on UPF consumption, expected around 2027.

2. The evidence base

A converging body of evidence

Researchers note these findings are now supported by a body of converging evidence using complementary scientific methodologies: meta-analyses, umbrella reviews, large cohorts followed over several years, cross-sectional studies, and, more recently, randomized controlled trials.

With highest levels of evidence the review found:

Class I: convincing evidence; Class II: highly suggestive / very likely evidence

Meta-analyses of 15 outcomes found statistically significant associations with adverse health conditions for 12, including:

The authors conclude: The totality of evidence shows that the ultra-processed dietary pattern has displaced, and continues to displace, long-established patterns... several plausible mechanisms explain associations with increased chronic disease risk and Taken together, these findings support the thesis that the ultra-processed dietary pattern is a major driver of the escalating global burden of diet-related chronic diseases.

The Lancet Series states: Now is the time to act on Ultra-Processed-Foods (UPFs) as a global health issue.

A higher ultra processed food (UPF) intake is linked to a heightened risk of several major chronic health issues, such as digestive diseases, high blood pressure, and metabolic syndrome/diabetes, as well as death. Eating a lot of ultra processed foods was associated with higher risks of cardiovascular events (24%), cancer (12%), obesity/overweight (23%), metabolic syndrome/diabetes (24%), depression/anxiety (27%), digestive diseases (31%), high blood pressure (11%) and death from any cause (18%).

A pooled analysis of 51 prospective cohort studies covering 8,819,894 adults found that higher ultra-processed food (UPF) intake is linked to a meaningfully greater risk of cardiovascular disease, cancer, diabetes, digestive disease, depression, and death.

Another systematic review included 41 prospective cohort studies spanning the Americas, Europe, Asia and Oceania assessing the association between ultra-processed foods and health outcomes.

Dose-response - no clear safe threshold

Every extra 100 g consumed was associated with correspondingly greater risks. Further analyses showed that each additional 100 g/day consumed was associated with greater risks of cardiovascular events (14%), cancer (4%), death from any cause (3%), and metabolic syndrome/diabetes (2%).

This was presented at ACC Asia 2025: Consumption of ultra-processed foods, such as sugar-sweetened beverages, breads, potato chips and packaged cookies, may be associated with adverse health outcomes, including hypertension, cancer, digestive diseases and adverse cardiovascular events.

High consumption of ultra-processed foods is associated with an increased risk of numerous chronic diseases, including obesity, type 2 diabetes, cardiovascular and cerebrovascular diseases, hypertension, dyslipidemia, as well as certain cancers. Research also points to associations with depressive symptoms, cognitive disorders, sleep disturbances, and higher overall mortality.

From the NutriNet-Santé cohort, one of the largest nutrition cohorts in the world: an increase of just 10% in the proportion of ultra-processed foods in the diet is associated with +12% risk of overall cancer, +15% risk of type 2 diabetes, +11% risk of overweight. These associations follow a dose-response pattern: the greater the proportion of ultra-processed foods in the diet, the higher the risk tends to be.

3. Why would processing itself be harmful? Mechanisms beyond nutrients

For a long time, these effects were attributed solely to their poor nutritional composition: too much sugar, salt, or fat. However, recent research suggests a more complex reality. Several studies show that the negative effects of ultra-processed foods persist even when calorie intake and nutritional content are comparable.

The Lancet lists several plausible mechanisms: Multiple nutrient imbalances, Overeating, Increased intake of toxic compounds, Exposure to potentially harmful additives and additive mixtures.

Emerging evidence suggests that the combination of multiple additives may exert a 'cocktail effect' on human health, while lab studies have shown that the extensively altered physical composition of UPFs may adversely affect the gut microbiome, and promote inflammation and insulin resistance. Several compounds that may form during food processing, such as acrylamide—a contaminant formed in heat-treated processed foods—and acrolein, generated during fat heating—have been associated with a higher incidence of cardiovascular disease.

Key experimental evidence:

4. Public health framing: a hazard requiring policy, not just individual choice

The Lancet series argues Improving diets cannot rely on consumer behaviour change alone —it also requires policies that regulate UPF marketing and production, confront corporate power, and reshape food systems to prioritise health, justice, and sustainability, over corporate profits.

It calls to Prioritise UPFs as a global health issue. Political action on UPFs has low priority despite the chronic disease burden; viewing them as commercially driven, like tobacco, shifts blame to corporate accountability.

Between 1962 and 2021, of the US$2.9 trillion in shareholder payouts by corporations operating across all food sectors, more than 50% was distributed by UPF manufacturers alone, giving surplus resources for globally coordinated influence on policy makers and intensive marketing.

The U.S. FDA and USDA in mid-2025 opened a formal request for information to help develop a uniform definition of ultra-processed foods as a step toward labeling and regulation, while Brazil has moved to require 90% of school food to be fresh or minimally processed by 2026.

5. Nuance and limitations

Scientists caution that not all discussion is settled:

Bottom line: Multiple independent umbrella reviews, a 2025-2026 pooled analysis of ~8.8 million people, and The Lancet's November 2025 series of 104 studies converge on the conclusion that diets high in UPFs are consistently associated with higher risks of obesity, type 2 diabetes, cardiovascular disease, depression, cancer, digestive diseases, and premature death, with risk rising dose-dependently. Authors conclude public health policies and actions are justified at all levels to preserve, protect, and promote diets based on whole foods, and that reducing consumption of UPFs and replacing them with minimally processed alternatives may be relevant for chronic disease prevention.