Are ultra-processed foods a public health hazard?

Ultra-processed foods are now front-page public health news — I'll gather the latest evidence on their risks and what health agencies are saying.

Yes, the majority of current evidence and major health authorities now treat diets high in ultra-processed foods (UPFs) as a public health hazard, though debate continues about definition and causation.

1. What are ultra-processed foods?

The most widely used definition is the NOVA classification:

Other descriptions used in recent meta-analyses:

> Ultra-processed foods are defined as ready-to-eat or heat-and-serve products that have undergone extensive industrial processing. Typically, they contain a range of additives, are energy-dense and high in sugar and salt but low in dietary fiber, protein, vitamins and minerals

Examples include candy and packaged snacks, described as “ready-to-eat or heat-and-serve products that undergo extensive industrial processing … often containing multiple additives,”

2. How widespread is consumption?

Global UPF consumption has increased over the last several decades.

The energy contribution of UPFs to diets has surged globally over recent decades 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

3. Evidence linking UPFs to disease and death

Largest recent meta-analysis

A pooled data analysis published in the open-access journal Family Medicine and Community Health found:

> 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

Dose-response findings:

> High consumption 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%).

> Further analyses showed that each additional 100 g/day (3.5 ounces per day) consumed was associated with greater risks of cardiovascular events (14%), cancer (4%), death from any cause (3%) and metabolic syndrome/diabetes (2%).

> And every 10% increase in weight/energy intake was associated with a 16% greater risk of metabolic syndrome/diabetes

The Lancet Series on UPFs and Human Health (2025)

A systematic review of 104 studies found 92 showing an association between the ultra-processed dietary pattern and increased risk of one or more chronic disease outcomes. Meta-analyses of 15 outcomes found statistically significant associations with adverse health conditions for 12, including:

The authors conclude:

> 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. Public health policies and actions are justified at all levels to preserve, protect, and promote diets based on whole foods

And call it a global health issue:

> Now is the time to act on Ultra-Processed-Foods (UPFs) as a global health issue.

BMJ Umbrella Review (2024)

A multicentre prospective cohort analysis in nine European countries published in The Lancet in January 2025, including 428,728 participants, found that ultra processed foods were positively associated with all-cause mortality, as well as mortality from circulatory diseases, cerebrovascular disease, ischemic heart disease, digestive diseases, and Parkinson’s disease

4. Plausible mechanisms

Researchers propose several mechanisms explain associations with increased chronic disease risk, including:

Specifically:

> Emerging evidence suggests that the combination of multiple additives may exert a "cocktail effect" on human health, while laboratory 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

Professional societies converge on pattern-based dietary recommendations: the American Heart Association (AHA) advises choosing MPFs over UPFs within heart-healthy diets

5. Official public health positions

The Lancet series argues that:

> 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.

Noting corporate power:

> 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.

6. Caveats and limitations

The evidence is largely observational, so causation is not proven:

> The researchers acknowledge various limitations to their findings, including the reliance of all the included studies on subjective dietary assessments and the exclusion of participants younger than 18.

And UPF intake often occurs in the context of broader lifestyle and behavioral patterns that are difficult to fully adjust for

Critics also note classification problems:

> “It is necessary to recognize that the NOVA Classification emphasizes the degree and purpose of food processing rather than nutritional composition,” the authors wrote.

While NOVA does not determine a finished product's nutritional content and may misidentify fortified foods as ultra-processed

Not all UPFs carry equal risk; the AHA acknowledges labelling foods as ‘ultra-processed’ can be misleading when nutrient-dense items are also included (e.g. nut butters), and research suggests different categories of UPFs show different relationships with mortality.

Bottom line

Based on systematic reviews covering ~9-10 million people across continents, high consumption of UPFs is consistently associated with 18-31% higher risks of cardiovascular events, type 2 diabetes, obesity, depression, digestive diseases, cancer, and premature death, with risk increasing in a dose-response manner per 100g or per 10% energy increase. Major bodies - The Lancet, BMJ, and the American Heart Association - now describe the ultra-processed dietary pattern as a major driver of diet-related chronic disease and a global health issue justifying policy action, including taxation, marketing restrictions, front-of-pack labelling, and promotion of minimally processed whole foods.

Reducing UPFs and replacing them with minimally processed alternatives may be relevant for chronic disease prevention and primary care management