Are ultra-processed foods a public health hazard?

Yes, a substantial and growing body of evidence indicates that high consumption of ultra-processed foods (UPFs) constitutes a significant public health hazard, contributing to the global rise in diet-related chronic diseases, though nuances and criticisms of the concept exist.[1]

What Are Ultra-Processed Foods?

UPFs are defined primarily by the NOVA classification system (developed by Brazilian researchers including Carlos Monteiro around 2009). They are industrial formulations made mostly or entirely from substances extracted from foods (e.g., oils, fats, sugars, starches, protein isolates) or derived from food constituents, combined with additives (flavors, colors, emulsifiers, preservatives) not typically used in home cooking. They contain little to no intact whole foods and are designed for convenience, hyper-palatability, long shelf life, and profitability.[2]

Examples include soft drinks, packaged snacks/chips, instant noodles, many ready meals, reconstituted meats, confectionery, many breakfast cereals, and some plant-based alternatives. They differ from unprocessed/minimally processed foods (e.g., fresh produce, plain yogurt), processed culinary ingredients (e.g., oils, sugar), and processed foods (e.g., canned vegetables, cheese).

In high-income countries like the US, UPFs often provide over 50–60% of adults’ calories (higher for children/teens, sometimes ~67–70%), and their share of diets is rising globally, including in low- and middle-income countries. Nearly 75% of the US food supply is estimated to be ultra-processed in some assessments.[3]

Evidence of Health Risks

Multiple large-scale reviews link higher UPF intake to worse outcomes:

Mechanisms (plausible and emerging) include: promotion of overeating; poor nutrient density (high free sugars, unhealthy fats, salt; low fiber/micronutrients); additives and processing byproducts (e.g., emulsifiers affecting gut microbiome, advanced glycation end-products, packaging contaminants); inflammation, dysglycemia, microbiome dysbiosis; and displacement of protective whole foods. Some effects appear independent of nutrient content alone.[2]

Processed meats (often UPFs) are classified by WHO/IARC as Group 1 carcinogens for colorectal cancer. Sugar-sweetened beverages show particularly strong harm links.[3]

Criticisms, Nuances, and Limitations

The evidence is not without caveats, and the UPF concept faces pushback:

Authoritative bodies like PAHO/FAO have used NOVA; WHO is developing guidelines on UPF consumption (as of 2025 calls for experts) and has highlighted them among commercial determinants of noncommunicable diseases. Some national guidelines (e.g., Brazil) incorporate processing concepts. The American Heart Association has noted nuance (not all UPFs unhealthy).[7]

Public Health Implications

Experts in the Lancet series and elsewhere argue the evidence justifies urgent action now—while more mechanistic and causal research continues—rather than waiting. Recommended approaches include: integrating UPFs into policies on high-fat/sugar/salt foods; taxes, warning labels, marketing restrictions (especially to children); reformulating school meals and food assistance; promoting whole/minimally processed foods and culinary skills; addressing commercial influences; and monitoring. High UPF intake worsens inequities and strains health systems via obesity, diabetes, CVD, etc.[1]

In short: Diets dominated by UPFs are strongly associated with poorer health outcomes and are widely viewed by public health experts as a major, addressable hazard contributing to the chronic disease epidemic. Reducing intake in favor of fresh, whole, and minimally processed foods is advisable for most people. Individual risk varies, and complete avoidance may not be practical or necessary for all items—prioritize quality, variety, and overall pattern. Consult evidence-based guidelines or professionals for personal advice, as research evolves.