Are ultra-processed foods a public health hazard?

Short answer: Yes, the evidence strongly suggests ultra-processed foods (UPFs) are a significant public health concern, though some scientific debate remains about mechanisms and precise definitions.

The Case That UPFs Are Harmful

Broad disease associations. Multiple systematic reviews and meta-analyses of large cohort studies have found consistent links between high UPF consumption and numerous health problems. A consistently positive association between high UPF intake and increased risk of developing diabetes (37%), hypertension (32%), hypertriglyceridemia (47%), low HDL cholesterol concentration (43%), and obesity (32%) was observed. Another major meta-analysis found highest UPF consumption was associated with increased risk of all-cause mortality in five studies, increased risk of CVD in three studies, cerebrovascular disease in two studies, and depression in two studies.

Mortality impact. A 2025 global study found that each 10% increase in ultra-processed food intake increases the risk of early death by 3% (between the ages of 30 and 69), following a "linear, dose-response relationship". The researchers estimated potentially 124,000 Americans die prematurely every two years due to ultra-processed food consumption.

Emerging mechanisms. 2025 research has moved beyond correlation toward causation. A 2025 randomized controlled trial has shown the harmful effects of UPFs on weight gain and metabolic and reproductive health, regardless of excessive caloric intake. Scientists are also investigating food additives as a mechanism—an experimental study on mice found two widely consumed food additive emulsifiers caused transgenerational microbiota alteration that led to increased long-term susceptibility to metabolic and inflammatory diseases.

Broader disease list. Beyond cardiometabolic conditions, research links UPFs to Type 2 diabetes, depression, and heart, kidney, and gastrointestinal diseases, as well as emerging links to colorectal cancer—a study led by Harvard T.H. Chan School of Public Health found younger women who eat more UPF, including highly processed bread, breakfast food and soda, may be more likely to develop colorectal cancer, relying on a robust data set representing nearly 30,000 nurses. Reviews have also found associations with kidney disease—the sale and consumption of these foods have been increasing despite their associations with increased risk for several non-communicable diseases, including chronic kidney disease—and even neurological conditions, where 4 of 5 studies demonstrated a risk association between the consumption of ultra-processed foods and the development of Alzheimer's disease.

Policy responses reflect the concern. In 2025, U.S. health agencies stated plainly that "Ultra-processed foods are driving our chronic disease epidemic," according to HHS Secretary Robert F. Kennedy, Jr., who said "We must act boldly to eliminate the root causes of chronic illness and improve the health of our food supply". A landmark 2025 Lancet series went further, concluding that although more research on UPFs will continue to be valuable, the current science is already strong enough to justify immediate public health action, and warning that waiting for further studies would allow UPFs to gain an even stronger hold in global diets. At the state level, 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 to California schoolchildren in the 2025–2026 school year.

Important Caveats and Nuance

Not all UPFs are equal. Researchers caution against treating the category as monolithic: some UPFs (e.g., certain wholegrain breads, low-sugar yoghurts, tomato sauces, nut/bean spreads) can contribute to healthy patterns and affordability, and should be monitored and reformulated if harms emerge. Similarly, one review noted processing level and nutrient quality should be considered together, focusing solely on either risks oversimplification.

Evidence quality varies. Some reviews urge caution in interpretation. One meta-analysis noted that these data have several limitations due to the meta-evidence of low quality and the fact that the level of risk consistently changes depending on the methodology used to assess UPF intake. Therefore, caution should be used when interpreting and extrapolating the results. Official dietary guidance bodies have also been cautious: the 2025–2030 Dietary Guidelines Advisory Committee initially judged UPF evidence too limited for formal recommendations given definitional and exposure inconsistencies.

Measurement challenges. Classification remains inconsistent across studies, as the application of NOVA to such dietary surveys is often inconsistent with incomplete ingredient information forcing research to make assumptions that risk misclassification. This is part of why the FDA and USDA in 2025 launched an effort to allow for consistency in research and policy... seeking public information on what factors and criteria should be included in a definition of ultra-processed foods.

Socioeconomic complexity. Part of what makes UPFs a public health challenge is that they aren't just a personal choice issue—they're structurally embedded in food systems. UPFs are shelf stable unlike fresh produce, save time, effort, and mental energy while cooking, and are more affordable—costing 55 cents per 100 calories, compared with $1.45 for unprocessed foods. This affordability gap means UPF are frequently more affordable than less-processed foods or fresh produce, and their low cost and wide availability may drive health disparities among populations who already face hunger, undernutrition and higher rates of chronic disease.

Industry influence complicates policy. Some researchers argue regulatory inaction stems partly from corporate interests, noting excessive influence of UPF manufacturers in committees advising politicians, who engage in high-profile health promotion while simultaneously lobbying against regulatory measures.

Bottom Line

The weight of evidence—spanning epidemiology, clinical trials, and mechanistic research—strongly supports classifying high UPF consumption as a genuine public health hazard linked to obesity, diabetes, cardiovascular disease, certain cancers, and premature death. However, the field is still refining exactly why UPFs are harmful (nutrient profile vs. additives vs. processing itself vs. displacement of whole foods) and which UPFs pose the greatest risk, making nuanced, food-specific policy more useful than blanket condemnation of "processed food" as a whole category.