Are ultra-processed foods a public health hazard?

Ultra-processed foods and public health - I'll pull the latest evidence on their health risks.

Yes - the growing scientific consensus is that diets high in ultra-processed foods (UPFs) represent a major public health hazard, although debate remains over definitions and whether all UPFs are equally harmful.

1. What are ultra-processed foods?

The term comes from the NOVA classification system, developed in 2009 by Brazilian researchers.

•The NOVA classification defines ultra-processed foods (UPFs) as "formulations of ingredients, mostly of exclusive industrial use, that result from a series of industrial processes."

•More specifically, 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)"

They are typically described as:

> Often high in sugar, salt, and fat; low in fibre, protein, and micronutrients; and containing additives, emulsifiers, stabilisers, colourants, and artificial sweeteners, UPFs generally having a poor nutrient profile.

Examples include commercially produced breads, sugar-sweetened beverages, potato chips, chocolate confectionery, candy, packaged cookies, etc., as well as deli meat, microwaveable dinners, or chips with long ingredient lists.

2. How widespread is consumption?

UPFs now dominate diets in high-income countries:

•At present, ultra-processed foods are estimated to account for approximately 57-60% of daily energy intake in the US and UK

•In the US, ultra-processed food consumption grew from 53.5 percent of calories in 2001-2002 to 57 percent in 2017-2018, while consumption of whole foods decreased from 32.7 percent to 27.4 percent

•In the UK in 2008-2009, average UPF consumption was 53% of total energy intake

3. Evidence linking UPFs to adverse health outcomes

Large epidemiological reviews have found consistent associations.

Largest umbrella review to date:
> 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.
> 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 with asthma, gastrointestinal disease, some cancers, and other issues were considered limited and needing further investigation.

Recent systematic review - ACC Asia 2025:
The systematic review included 41 prospective cohort studies spanning the Americas, Europe, Asia and Oceania involving a total of 8,286,940 adult patients.

> Each additional 100 g/day of ultra-processed food consumption was associated with a 14.5% higher risk of hypertension, 5.9% increased risk of cardiovascular events, 1.2% increased risk of cancer, 19.5% higher risk of digestive diseases and 2.6% higher risk of all-cause mortality.
> Researchers also observed increased risk of obesity/overweight, metabolic syndromes/diabetes and depression/anxiety.

GRADE assessment indicated high to moderate certainty for most outcomes, except low certainty for metabolic syndrome/diabetes.

Other studies have found:

•In addition to obesity and weight gain, ultraprocessed foods have also been linked to cancer and cardiovascular disease in recent large epidemiologic studies conducted in France.

•A Harvard study found those who ate the most ultra-processed foods had a 17% higher chance of developing cardiovascular disease compared with those who ate the least. The riskiest categories were sugary drinks and processed meats.

•A Harvard T.H. Chan School study found participants who ate the most ultra-processed food faced a 4% higher risk of all-cause mortality, as well as an 8% higher risk of mortality from neurodegenerative diseases. Processed meat was the type most strongly associated with increased risk.

•A 2024 review involving nearly 9.8 million participants concluded a diet of ultra-processed foods is associated with 32 adverse physical and mental health problems.

The Lancet describes UPFs as Strongly linked to poor health outcomes (increased risk of diet-related chronic diseases such as obesity, type 2 diabetes, cardiovascular disease, and certain cancers).

4. Why might they be hazardous - beyond nutrients?

Traditional explanations focus on:

> "Ultra-processed foods are characterized by high sugar, high salt, and other non-nutritive components, exhibiting low nutritional density yet high caloric content," and may contribute through dysregulation of blood lipid profiles, alterations in gut microbiota, promotion of obesity, systemic inflammation, oxidative stress and impairment of insulin sensitivity.

Newer research suggests risk remains even after accounting for nutritional quality:

> The researchers found that people who ate more ultra-processed foods had worse health outcomes, even after accounting for the overall nutritional quality of the foods.
> "The findings suggest ultra-processed-food factors beyond nutrients—such as changes to foods' cellular structure, loss of beneficial chemical compounds, additives, and chemicals from packaging—may create health risks"

5. Public health view

•The World Health Organization 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 brought together experts to develop a guideline on the consumption of ultra-processed foods, noting consumption has been associated with a myriad of negative health effects.

The perception among the public is also that UPFs are hazardous. A Cornell-led study found:

> More than 60% of survey respondents agreed that such foods are addictive and major causes of obesity, Type 2 diabetes and heart disease. Respondents perceived the health risks as less serious than cigarettes but roughly equivalent to alcohol and worse than fast food

Governments are considering measures including stringent food labeling regulations, requiring manufacturers to provide explicit ingredient disclosures, taxing unhealthy options, protecting children from marketing, and reducing salt, sugars and harmful fats in processed products.

6. Nuance and controversy

Not all experts agree that all UPFs should be treated as equally hazardous:

•In an Oct. 6 Washington Post op-ed, Harvard's David Ludwig wrote that ultra-processed foods are defined imprecisely and studies have not definitely shown causation

•Researchers have noted they do not believe it is appropriate to be advising consumers to avoid all UPFs and we await further evidence to inform consumer guidance on the need to limit consumption

•"But not all foods that fit the definition of ultra-processed are unhealthy," says Johns Hopkins researcher Julia Wolfson - for example, sweetened yogurt and whole grain breads are considered "ultra-processed" on the NOVA scale despite being nutrient-dense.

Nearly 100 observational studies and three different randomized controlled trials have linked overconsumption of ultra-processed foods to health harms, but most evidence remains observational, making it difficult to prove that processing itself - rather than overall diet quality, lifestyle, or socioeconomic factors - causes disease. The heterogeneity of the UPF category means risk varies substantially by food type, with sugary drinks and processed meats consistently showing the strongest associations.

Conclusion: Based on current large-scale epidemiological evidence, high consumption of ultra-processed foods - especially sugary drinks, processed meats, packaged snacks, and ready-to-eat meals - is widely regarded by researchers, Harvard, ACC, and WHO-related bodies as a public health hazard associated with higher risks of obesity, cardiovascular disease, type 2 diabetes, depression, and premature death. Mitigation strategies focus on reducing overall UPF intake and replacing them with minimally processed, whole foods, while ongoing research seeks to clarify which specific processing factors and additives drive harm and how to define and regulate UPFs more precisely.

This information is for educational purposes and not medical advice. For personal dietary guidance, consult a healthcare professional.

1.Ultra-processed foods: yet another wake-up call — https://www.thelancet.com/journals/landia/article/PIIS2213-8587(25)00139-1/fulltext

Citations (3)

1thelancet.comAcademic
Ultra-processed foods: yet another wake-up call
Backs: “several food additives used to make the product hyperpalatable)". They are typically described as: Often high in sugar, salt, and fat; low in fibre, protein, and micronutrients; and containing additives, emulsifiers, stabilisers, colourants, and artificial sweeteners, UPFs generally having a poor nutrient profile.”
2acc.orgNonprofits and think tanks
Eating Ultra-Processed Foods May Harm Your Health - American College of Cardiology
Backs: “Often high in sugar, salt, and fat; low in fibre, protein, and micronutrients; and containing additives, emulsifiers, stabilisers, colourants, and artificial sweeteners, UPFs generally having a poor nutrient profile. Examples include commercially produced breads, sugar-sweetened beverages, potato chips, chocolate…”
3harvard.eduAcademic
More evidence that ultra-processed foods harm health - Harvard Health
Backs: “Examples include commercially produced breads, sugar-sweetened beverages, potato chips, chocolate confectionery, candy, packaged cookies, etc., as well as deli meat, microwaveable dinners, or chips with long ingredient lists.”