Are ultra-processed foods a public health hazard?

I'll examine the evidence on whether ultra-processed foods pose a public health hazard.

Yes - major health agencies and the largest reviews of the evidence to date increasingly treat high consumption of ultra-processed foods (UPFs) as a public health hazard, though debate continues about definitions, mechanisms and causality.

1. What are ultra-processed foods?

As defined using the Nova food classification system, ultra-processed foods encompass a broad range of ready to eat products, including packaged snacks, carbonated soft drinks, instant noodles, and ready-made meals. These products are characterised as industrial formulations primarily composed of chemically modified substances extracted from foods, along with additives to enhance taste, texture, appearance, and durability, with minimal to no inclusion of whole foods.

Analyses of worldwide sales indicate a shift towards an increasingly ultra-processed global diet.

•Across high income countries, the share of dietary energy derived from ultra-processed foods ranges from 42% and 58% in Australia and the United States, respectively, to as low as 10% and 25% in Italy and South Korea

•In low and middle income countries such as Colombia and Mexico, for example, these figures range from 16% to 30% of total energy intake, respectively

•In the US it is estimated that approximately 70% of packaged products in the U.S. food supply are foods often considered ultra-processed, and that children get over 60% of their calories from such foods

2. What does the evidence show?

Largest review to date

Need more reasons to stop eating ultra-processed food? How about 32 of them? That's the number of health problems noted in the largest-ever review of studies about the dangers of diets high in ultra-processed foods. The findings, published online Feb. 28, 2024, by The BMJ, come from a review of 45 analyses published in the last three years, involving about 10 million people in total

That umbrella review systematically searched MEDLINE, PsycINFO, Embase and Cochrane from 2009 to June 2023.

> 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. Associations between ultra-processed foods and asthma, gastrointestinal disease, some cancers, and other health issues were limited and need further investigation.

In detail:

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) and type 2 diabetes (dose-response risk ratio 1.12, 1.11 to 1.13), as well as higher risks of prevalent anxiety outcomes (odds ratio 1.48, 1.37 to 1.59) and combined common mental disorder outcomes (odds ratio 1.53, 1.43 to 1.63)

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), heart disease related mortality (hazard ratio 1.66, 1.51 to 1.84), type 2 diabetes (odds ratio 1.40, 1.23 to 1.59), and depressive outcomes (hazard ratio 1.22, 1.16 to 1.28), together with higher risks of prevalent adverse sleep related outcomes, wheezing, and obesity

A summary from the same body of research:

> High consumption of ultra-processed foods appears to increase the risk of all-cause mortality, cardiovascular disease (CVD)-related mortality, common mental disorders, overweight and obesity, and type 2 diabetes

Other studies support this pattern:

•Investigators have reported higher risk of incident hypertension, obesity, and all-cause mortality, and in the NutriNet-Santé study, consumption was prospectively linked to a higher risk of type 2 diabetes, incident cardiovascular disease, and all-cause mortality

•A 2024 Harvard-linked cohort found those who ate the most ultra-processed foods had a 17% higher chance of developing cardiovascular disease, with sugary drinks and processed meats the riskiest categories

•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

French food safety agency ANSES, after a systematic review, 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

3. Why is it considered a public health hazard?

Public health authorities point to three factors:

a) Plausible mechanisms: Some characteristics of ultra-processed foods include alterations to food matrices and textures, potential contaminants from packaging material and processing, and the presence of food additives and other industrial ingredients, as well as nutrient poor profiles (for example, higher energy, salt, sugar, and saturated fat, with lower levels of dietary fibre, micronutrients, and vitamins). Emerging evidence suggests such properties may act through changes to the gut microbiome and increased inflammation.

b) Population-level exposure: Easy availability and access to a wide variety of low-cost, aggressively marketed pre-packaged processed or ultra- processed foods high in fat, sugar and salt are changing dietary patterns of people and fuelling obesity

c) Consensus for action:

•Mounting evidence from epidemiological studies links consumption of ultra-processed food to poorer cardiometabolic health - Existing evidence is sufficiently strong to warrant immediate public health actions to help citizens identify ultra-processed foods and limit their exposure

•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 for improved human health

•Consumption of such highly processed or “ultra-processed” foods has been associated with a myriad of negative health effects. WHO and the International Agency for Research on Cancer endorse public health strategies to limit the intake of components commonly present in ultra-processed foods, including high levels of added sugar and non-sugar sweeteners

•WHO has convened a Guideline Development Group to develop a guideline on the consumption of ultra-processed foods

•In the US, HHS, FDA and USDA in July 2025 said: "The threats posed to our health by foods often considered ultra-processed are clear and convincing, making it imperative that we work in lockstep with our federal partners to advance, for the first time ever, a uniform definition of ultra-processed foods" and "Ultra-processed foods are driving our chronic disease epidemic"

Proposed public health measures include product reformulation towards a healthier nutrient composition, fiscal policies that target unhealthy foods and subsidizes healthier foods, restricting marketing of foods and non-alcoholic beverages high in fat, sugar and salt and labelling of food products

4. Important caveats and debate

The hazard framing is not without criticism:

Quality of evidence is largely low: Overall, using the GRADE framework, 22 pooled analyses were rated as low quality, with 19 rated as very low quality and four rated as moderate quality. Most data come from observational cohort and cross-sectional studies, not randomized trials, so causality cannot be proven.

•Numerous observational studies have shown associations between the consumption of UPFs and an increased risk of obesity, and obesity-related health problems such as type 2 diabetes, cardiovascular diseases, cancers and all-cause mortality. However, there is still little evidence establishing the causality between consumption of UPFs and obesity

The NOVA classification is contested:

•Others noted that the classification system that has come to be used for identifying UPFs – the NOVA Food Classification system – is too mushy, confusing, and, ultimately unhelpful

•When hundreds of evaluators were asked to classify with NOVA 231 foods (52% with specified ingredients), only one food was assigned to the same NOVA category by all evaluators and these were nutrition/food science experts!

•The Nova system has come under scrutiny for not taking into account nutrients known to be unhealthy, such as fat, salt and sugar

•NOVA does not take a product's nutrient health profile into consideration. Thus, it wasn't designed to really distinguish those healthier category 4 products, like whole wheat bread, yogurt and... Under NOVA, those are all considered ultra-processed foods

Critics argue this lumps together nutritionally very different foods (e.g., sugary soda vs. fortified whole-grain bread or unsweetened yogurt) and that health risks may be driven more by nutrient content (sugar, salt, saturated fat, low fiber) and overall dietary pattern than by processing per se. Researchers note scientists are still debating what's driving those risks: the nutritional quality vs. the industrial processing and additives.

Heterogeneity: Not all UPFs appear equally harmful. Harvard studies suggest sugary drinks and processed meats carry the strongest links to cardiovascular mortality and early death, while some UPF subgroups show weaker or no associations.

5. Bottom line

•There is consistent, growing epidemiological evidence that higher intake of ultra-processed foods is associated with higher risks of obesity, type 2 diabetes, cardiovascular disease and mortality, depression/anxiety, and other adverse outcomes.

•Public health bodies (WHO, FDA, HHS, USDA, national academies) increasingly describe UPF overconsumption as a modifiable risk factor and public health concern warranting population-level policies, even as they work to create a uniform definition.

•However, the evidence base is predominantly observational and graded as low to very low certainty, and the tool used to define UPFs (NOVA) is imperfect and does not distinguish nutrient quality. This means the hazard is best understood as associated with diets high in UPFs - particularly those high in added sugars, sodium, unhealthy fats and additives and low in whole foods - rather than every single food labeled ultra-processed.

Current guidance from most experts aligns: reducing UPFs, especially sugar-sweetened beverages, processed meats, and packaged snacks high in sugar/salt/fat, and replacing them with minimally processed foods (fruits, vegetables, whole grains, legumes, nuts, fresh meats, plain dairy) is likely to improve diet quality and lower chronic disease risk, while research on mechanisms and clearer regulatory definitions continues.

This information is educational and does not replace professional medical advice. If you have specific dietary concerns, consult a healthcare professional or registered dietitian.

Citations (3)

1bmj.comAcademic
Ultra-processed food exposure and adverse health outcomes: umbrella review of epidemiological meta-analyses
Backs: “Yes - major health agencies and the largest reviews of the evidence to date increasingly treat high consumption of ultra-processed foods (UPFs) as a public health hazard, though debate continues about definitions, mechanisms and causality. 1. What are ultra-processed foods? As defined using the Nova food…”
2fda.govGovernment
HHS, FDA and USDA Address the Health Risks of Ultra-Processed Foods
Backs: “In low and middle income countries such as Colombia and Mexico, for example, these figures range from 16% to 30% of total energy intake, respectively. In the US it is estimated that approximately 70% of packaged products in the U.S. food supply are foods often considered ultra-processed, and that children get over 60%…”
3harvard.eduAcademic
More evidence that ultra-processed foods harm health - Harvard Health
Backs: “That's the number of health problems noted in the largest-ever review of studies about the dangers of diets high in ultra-processed foods. The findings, published online Feb. 28, 2024, by The BMJ, come from a review of 45 analyses published in the last three years, involving about 10 million people in total”