Are ultra-processed foods a public health hazard?

Ultra-processed foods are under intense scrutiny — I'll review the latest evidence on whether they pose a public health hazard.

Yes - major public health agencies and large reviews of evidence now treat high consumption of ultra-processed foods (UPFs) as a public health hazard, although evidence is nuanced and not all UPFs appear equally harmful.

1. What are ultra-processed foods?

The most widely used framework is the NOVA Food Classification System, developed in 2009 by Carlos Monteiro. Under NOVA:

> Ultra-Processed Foods (UPF; NOVA "Group 4") refers to "industrial formulations made entirely or mostly from substances extracted from foods (oils, fats, sugar, starch, and proteins), derived from food constituents (hydrogenated fats and modified starch), or synthesized in laboratories from food substrates or other organic sources (flavor enhancers, colors, and several food additives used to make the product hyperpalatable)"

Other descriptions characterize them as:

> industrial formulations of processed food substances (oils, fats, sugars, starch, protein isolates) that contain little or no whole foods and typically include flavorings, colorings, emulsifiers, and other cosmetic additives

Typical examples include packaged snacks, carbonated soft drinks, instant noodles, and ready-made meals, carbonated drinks, mass produced packaged breads, biscuits, breakfast cereals, energy drinks, infant formula, nuggets, sausages, instant soups.

There is no single authoritative federal definition in the US yet. In July 2025 the U.S. Department of Health and Human Services, FDA and USDA issued a joint Request for Information to gather data to help establish a federally recognized uniform definition for ultra-processed foods.

2. How widespread is exposure?

3. Evidence linking UPFs to adverse health outcomes

Largest reviews to date

The largest-ever umbrella review, published Feb. 28, 2024 in The BMJ, reviewed 45 analyses published in the last three years, involving about 10 million people in total:

> Overall, direct associations were found between exposure to ultra-processed foods and 32 (71%) health parameters spanning mortality, cancer, and mental, respiratory, cardiovascular, gastrointestinal, and metabolic health outcomes.

When scientists graded the evidence, they found the most convincing or highly suggestive evidence linked diets rich in ultra-processed foods with increased risks for premature death, cardiovascular disease, mental health disorders, diabetes, obesity, and sleep problems.

In detail, using pre-specified evidence classification:

> convincing evidence (class I) supported direct associations between greater ultra-processed food exposure and higher risks of incident cardiovascular disease related mortality (risk ratio 1.50, 95% confidence interval 1.37 to 1.63; GRADE=very low) and type 2 diabetes (dose-response risk ratio 1.12, 1.11 to 1.13; moderate), as well as higher risks of prevalent anxiety outcomes (odds ratio 1.48, 1.37 to 1.59; low) and combined common mental disorder outcomes (odds ratio 1.53, 1.43 to 1.63; low)

> Highly suggestive (class II) evidence indicated that greater exposure to ultra-processed foods was directly associated with higher risks of incident all cause mortality (risk ratio 1.21, 1.15 to 1.27; low), heart disease related mortality (hazard ratio 1.66, 1.51 to 1.84; low), type 2 diabetes (odds ratio 1.40, 1.23 to 1.59; very low), and depressive outcomes (hazard ratio 1.22, 1.16 to 1.28; low)

The authors concluded:

> Greater exposure to ultra-processed food was associated with a higher risk of adverse health outcomes, especially cardiometabolic, common mental disorder, and mortality outcomes. These findings provide a rationale to develop and evaluate the effectiveness of using population based and public health measures to target and reduce dietary exposure to ultra-processed foods

Other large summaries agree:

> Growing evidence confirms a link between consumption of ultra-processed food and drinks and non-communicable diseases

> 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

The French food safety agency ANSES concluded, albeit with a low weight of evidence, that a higher level of consumption of foods classified as ultra-processed under the Nova framework is associated with a higher risk of mortality and chronic diseases such as type 2 diabetes, overweight, obesity, cardioneurovascular diseases, and breast and colorectal cancer

US health authorities state:

> Dozens of scientific studies have found links between the consumption of foods often considered ultra-processed with numerous adverse health outcomes, including cardiovascular disease, Type 2 diabetes, cancer, obesity and neurological disorders

FDA Commissioner Marty Makary stated: "The threats posed to our health by foods often considered ultra-processed are clear and convincing"

The World Health Organization notes:

> Consumption of such highly processed or “ultra-processed” foods has been associated with a myriad of negative health effects
and has formed a guideline development group to provide global guidance on consumption of ultra-processed foods.

Evidence quality and limitations

4. Proposed mechanisms why UPFs may be hazardous

Researchers propose several overlapping pathways:

5. Important nuance: Not all UPFs are equal

Experts increasingly emphasize nuance:

> But not all foods that fit the definition of ultra-processed are unhealthy, says Julia Wolfson, an associate professor at the Johns Hopkins Bloomberg School of Public Health. For instance, packaged whole grain breads, plant-based milks and some yogurts are considered ultra-processed, but they can be beneficial for health

Recent analyses have found divergent effects within UPF categories:

> The study found that sugary and artificially sweetened drinks, along with processed meats, were linked to a greater risk of cardiovascular disease and coronary heart disease. ... But cereals, savory snacks, and yogurt and dairy-based desserts were linked to a lower risk of these diseases

Similarly, ultra-processed cereals and breads were also linked to a lower stroke risk in some studies, while critics note that NOVA sweeps in items that are nutritionally sound or even beneficial.

This has led to debate whether the harm comes from ultra-processing per se (industrial formulations, additives, neo-formed contaminants) versus simply the poor nutritional composition (sugar, salt, saturated fat) that often accompanies it. Some researchers argue classifying by processing alone is too blunt and may distract from nutrient-based guidance.

However, public health scholars argue that even if ultra-processing itself is not inherently toxic, the overall dietary pattern high in UPFs displaces minimally processed foods and drives poor diet quality, and therefore warrants population-level action regardless of exact mechanism.

6. Public health implications

Given the consistency of associations across countries and study designs, many authorities argue precautionary public health action is justified while mechanistic research continues:

For individuals, guidance from Harvard and other institutions is pragmatic: replace ready-to-eat products such as deli meat, microwaveable dinners, or chips with long ingredient lists with less-processed options or whole foods when possible, but not to avoid all foods labeled ultra-processed — for example, whole-grain bread or unsweetened yogurt with whole foods may be acceptable when whole-food alternatives are inaccessible due to cost or time.

Bottom line: While randomized trial evidence is still limited and evidence quality is mostly low, the large and growing observational literature consistently links high UPF consumption — especially sugary drinks and processed meats — to higher risks of obesity, type 2 diabetes, cardiovascular disease, depression, and early death. For that reason, HHS/FDA, WHO, and many academic groups now describe excess UPF consumption as a clear public health concern requiring definition, monitoring, and policy intervention, while acknowledging that not every food meeting the technical NOVA definition carries the same risk.