An ultra-processed food (UPF) is a grouping of

processed food Food processing is the transformation of agricultural products into food, or of one form of food into other forms. Food processing takes many forms, from grinding grain into raw flour, home cooking, and complex industrial methods used in the mak ...

characterized by relatively involved methods of production. There is no simple definition of UPF, but they are generally understood to be an industrial creation derived from natural food or synthesized from other

organic compounds Some chemical authorities define an organic compound as a chemical compound that contains a carbon–hydrogen or carbon–carbon bond; others consider an organic compound to be any chemical compound that contains carbon. For example, carbon-co ...

. The resulting products are designed to be highly

profitable In economics, profit is the difference between revenue that an economic entity has received from its outputs and total costs of its inputs, also known as surplus value. It is equal to total revenue minus total cost, including both explicit an ...

, convenient, and hyperpalatable, often through

food additives Food additives are substances added to food to preserve flavor or enhance taste, appearance, or other sensory qualities. Some additives, such as vinegar ( pickling), salt ( salting), smoke (smoking) and sugar (crystallization), have been used for ...

such as

preservative A preservative is a substance or a chemical that is added to products such as food products, beverages, pharmaceutical drugs, paints, biological samples, cosmetics, wood, and many other products to prevent decomposition by microbial growth or ...

s, colourings, and flavourings. UPFs have often undergone processes such as moulding/extruding,

hydrogenation Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to redox, reduce or Saturated ...

, or

frying Frying is the cooking of food in cooking oil, oil or another fat. Similar to sautéing, pan-fried foods are generally turned over once or twice during cooking to make sure that the food is evenly cooked, using tongs or a spatula, whilst sautéed ...

. Ultra-processed foods first became ubiquitous in the 1980s, though the term "ultra-processed food" gained prominence from a 2009 paper by Brazilian researchers as part of the Nova classification system. In the Nova system, UPFs include most bread and other mass-produced baked goods, frozen pizza, instant noodles, flavored yogurt, fruit and milk drinks, diet products, baby food, and most of what is considered

junk food "Junk food" is a term used to describe food that is high in calorie#Nutrition, calories from macronutrients such as sugar and fat, and often also high in sodium, making it hyperpalatable, and low in dietary fiber, Protein (nutrient), protein, or m ...

. The Nova definition considers ingredients, processing, and how products are marketed; nutritional content is not evaluated. As of 2024, research into the effects of UPFs is rapidly evolving. Since the 1990s, UPF sales have consistently increased or remained high in most countries. While national data is limited, as of 2023, the United States and the United Kingdom lead the consumption rankings, with 58% and 57% of daily

calories The calorie is a unit of energy that originated from the caloric theory of heat. The large calorie, food calorie, dietary calorie, kilocalorie, or kilogram calorie is defined as the amount of heat needed to raise the temperature of one liter o ...

, respectively. Consumption varies widely across countries, ranging from 25% to 35%. Chile, France, Mexico, and Spain fall within this range, while Colombia, Italy, and Taiwan have consumption levels of 20% or less. Epidemiological data suggest that consumption of ultra-processed foods is associated with non-communicable diseases and

obesity Obesity is a medical condition, considered by multiple organizations to be a disease, in which excess Adipose tissue, body fat has accumulated to such an extent that it can potentially have negative effects on health. People are classifi ...

. A 2024

meta-analysis Meta-analysis is a method of synthesis of quantitative data from multiple independent studies addressing a common research question. An important part of this method involves computing a combined effect size across all of the studies. As such, th ...

published in ''

The BMJ ''The BMJ'' is a fortnightly peer-reviewed medical journal, published by BMJ Publishing Group Ltd, which in turn is wholly-owned by the British Medical Association (BMA). ''The BMJ'' has editorial freedom from the BMA. It is one of the world ...

'' identified 32 studies that associated UPF with negative health outcomes, though it also noted a possible heterogeneity among sub-groups of UPF. The specific mechanism of the effects was not clear. Some authors have criticised the concept of "ultra-processed foods" as poorly defined, and the Nova classification system as too focused on the type rather than the amount of food consumed. Other authors, mostly in the field of nutrition, have been critical of the lack of attributed mechanisms for the health effects, focusing on how the current research evidence does not provide specific explanations for how ultra-processed food affects body systems.

Definitions

Concerns about

food processing Food processing is the transformation of agricultural products into food, or of one form of food into other forms. Food processing takes many forms, from grinding grain into raw flour, home cooking, and complex industrial methods used in the mak ...

have existed since at least the

Industrial Revolution The Industrial Revolution, sometimes divided into the First Industrial Revolution and Second Industrial Revolution, was a transitional period of the global economy toward more widespread, efficient and stable manufacturing processes, succee ...

. The origin of ultra-processed food is more recent: Michael Pollan's influential book '' The Omnivore's Dilemma'' (2006) referred to highly processed industrial food as 'edible food-like substances'. Carlos Augusto Monteiro cited Pollan as an influence in coining the term 'ultra-processed food' in a 2009 commentary. Some sources have described UPF as "predigested food". Monteiro's team developed the Nova classification for grouping unprocessed and processed foods beginning in 2010, whose definition of ultra-processing became the most widely accepted, refined through successive publications. The identification of ultra-processed foods, as well as the category itself, is a subject of debate among nutrition and public health scientists, and other definitions have been proposed. A survey of systems for classifying levels of food processing in 2021 identified four 'defining themes': * Extent of change (from natural state) * Nature of change (properties, ingredients added) * Place of processing (where/by whom) * Purpose of processing (why, essential/cosmetic)

Monteiro's 2009 commentary

Carlos Monteiro, working with a team of researchers at the University of São Paulo, first published the concept of ultra-processed foods:

Ultra-processed foods are basically confections of group 2 ingredients ubstances extracted from whole foods typically combined with sophisticated use of additives, to make them edible, palatable, and habit-forming. They have no real resemblance to group 1 foods inimally processed foods although they may be shaped, labelled and marketed so as to seem wholesome and 'fresh'. Unlike the ingredients included in group 2, ultra-processed foods are typically not consumed with or as part of minimally processed foods, dishes and meals. On the contrary, they are designed to be ready-to-eat (sometimes with addition of liquid such as milk) or ready-to-heat, and are often consumed alone or in combination (such as savoury snacks with soft drinks, bread with burgers).

This definition is as much social as one based on specific ingredients, which makes the understanding of ultra-processed foods highly intuitive, even among untrained consumers. A letter responding to Monteiro's 2009 commentary suggested that the definition 'lacks precision', since it lacks the measurable definitions of traditional

food science Food science (or bromatology) is the basic science and applied science of food; its scope starts at overlap with agricultural science and nutritional science and leads through the scientific aspects of food safety and food processing, informing ...

. Because of this, researchers disagree whether the definition can form a valid basis for scientific investigation. Researchers have developed a quantitative definition for hyperpalatable food, but not for ultra-processed food.

Nova classification

Monteiro's team subsequently presented ultra-processed foods as a group in the Nova food classification system. The system focuses on

rather than foods types or

nutrient A nutrient is a substance used by an organism to survive, grow and reproduce. The requirement for dietary nutrient intake applies to animals, plants, fungi and protists. Nutrients can be incorporated into cells for metabolic purposes or excret ...

s. Nova categorizes foods into four groups: unprocessed or minimally processed foods, processed ingredients, processed foods, and ultra-processed foods. Nova is an open classification that refines its definitions gradually through scientific publications rather than through a central advisory board. The most recent overview of Nova defines ultra-processed food as:

Industrially manufactured food products made up of several ingredients (formulations) including sugar, oils, fats and salt (generally in combination and in higher amounts than in processed foods) and food substances of no or rare culinary use (such as
high-fructose corn syrup High-fructose corn syrup (HFCS), also known as glucose–fructose, isoglucose, and glucose–fructose syrup, is a sweetener made from corn starch. As in the production of conventional corn syrup, the starch is broken down into glucose by enzy ...
, hydrogenated oils, modified starches and protein isolates). Group 1 n- or minimally processedfoods are absent or represent a small proportion of the ingredients in the formulation. Processes enabling the manufacture of ultra-processed foods include industrial techniques such as
extrusion Extrusion is a process used to create objects of a fixed cross section (geometry), cross-sectional profile by pushing material through a Die (manufacturing), die of the desired cross-section. Its two main advantages over other manufacturing pro ...
, moulding and pre-frying; application of additives including those whose function is to make the final product palatable or hyperpalatable such as flavours, colourants, non-sugar sweeteners and
emulsifiers An emulsion is a mixture of two or more liquids that are normally immiscible (unmixable or unblendable) owing to liquid-liquid phase separation. Emulsions are part of a more general class of two-phase systems of matter called colloids. Although ...
; and sophisticated packaging, usually with synthetic materials. Processes and ingredients here are designed to create highly profitable (low-cost ingredients, long shelf-life, emphatic branding), convenient (ready-to-(h)eat or to drink), tasteful alternatives to all other Nova food groups and to freshly prepared dishes and meals.

Ultra-processed foods are further defined as measurably distinguishable from processed foods by ingredients "of no culinary use (varieties of sugars such as

fructose Fructose (), or fruit sugar, is a Ketose, ketonic monosaccharide, simple sugar found in many plants, where it is often bonded to glucose to form the disaccharide sucrose. It is one of the three dietary monosaccharides, along with glucose and gal ...

, high-fructose corn syrup, ' fruit juice concentrates',

invert sugar Inverted sugar syrup is a syrup mixture of the monosaccharides glucose and fructose, made by splitting disaccharide sucrose. This mixture's optical rotation is opposite to that of the original sugar, which is why it is called an ''invert'' sug ...

maltodextrin Maltodextrin is a name shared by two different families of chemicals. Both families are glucose polymers (also called ''dextrose polymers'' or ''Dextrin, dextrins''), but have little chemical or nutritional similarity. The digestible maltodextr ...

dextrose Glucose is a sugar with the molecular formula , which is often abbreviated as Glc. It is overall the most abundant monosaccharide, a subcategory of carbohydrates. It is mainly made by plants and most algae during photosynthesis from water an ...

and

lactose Lactose is a disaccharide composed of galactose and glucose and has the molecular formula C12H22O11. Lactose makes up around 2–8% of milk (by mass). The name comes from (Genitive case, gen. ), the Latin word for milk, plus the suffix ''-o ...

; modified starches; modified oils such as hydrogenated or interesterified oils; and protein sources such as hydrolysed proteins, soya protein isolate,

gluten Gluten is a structural protein naturally found in certain Cereal, cereal grains. The term ''gluten'' usually refers to the elastic network of a wheat grain's proteins, gliadin and glutenin primarily, that forms readily with the addition of water ...

casein Casein ( , from Latin ''caseus'' "cheese") is a family of related phosphoproteins (CSN1S1, αS1, aS2, CSN2, β, K-casein, κ) that are commonly found in mammalian milk, comprising about 80% of the proteins in cow's milk and between 20% and 60% of ...

whey protein Whey protein is a mixture of proteins isolated from whey, the liquid material created as a by-product of cheese production. The proteins consist of α-lactalbumin, β-lactoglobulin, serum albumin and immunoglobulins. Glycomacropeptide also m ...

and '

mechanically separated meat Mechanically separated meat (MSM), mechanically recovered/reclaimed meat (MRM), or mechanically deboned meat (MDM) is a paste-like meat product produced by forcing pureed or ground beef, pork, mutton, turkey or chicken under high pressure t ...

') or of additives with cosmetic functions (flavours, flavour enhancers, colours, emulsifiers, emulsifying salts, sweeteners, thickeners and anti-foaming, bulking, carbonating, foaming, gelling and glazing agents) in their list of ingredients." The Nova definition of ultra-processed food does not comment on the nutritional content of food and is not intended to be used for

nutrient profiling Nutrient profiling, also nutritional profiling, is the science of classifying or ranking foods by their nutritional composition in order to promote health and prevent disease. A common use of nutrient profiling is in the creation of nutritional rat ...

International Agency for Research on Cancer (IARC)

The

International Agency for Research on Cancer The International Agency for Research on Cancer (IARC; ) is an intergovernmental agency forming part of the World Health Organization of the United Nations. Its role is to conduct and coordinate research into the causes of cancer. It also cance ...

, an intergovernmental agency that forms part of the

World Health Organization The World Health Organization (WHO) is a list of specialized agencies of the United Nations, specialized agency of the United Nations which coordinates responses to international public health issues and emergencies. It is headquartered in Gen ...

, classifies foods by their degree of processing. This system breaks food into 'non-processed', 'moderately processed', and 'highly processed' food. The system does not take into account the nature or purpose of changes.

Siga Index

The Siga Index is a classification system for processed foods developed in

France France, officially the French Republic, is a country located primarily in Western Europe. Overseas France, Its overseas regions and territories include French Guiana in South America, Saint Pierre and Miquelon in the Atlantic Ocean#North Atlan ...

. It is based on the degree of processing and the nutritional quality of foods, using a holistic and reductionist approach. The Siga Index assigns a score from 1 to 100 to each food product, where higher scores indicate higher nutritional quality and lower processing. The Siga Index also defines ultra-processed foods (UPFs) as those with a score below 40, which are considered to have low nutritional value and high levels of additives, preservatives, and artificial ingredients.

International Food Information Council (IFIC)

The

International Food Information Council Founded in 1985, the International Food Information Council (IFIC) is a nonprofit organization supported by the food, beverage, and agricultural industries.natural food.

Profitability

Ultra-processed foods often use less expensive ingredients, allowing ultra-processed food to be priced lower. Furthermore, ultra-processed foods are more consistently available in stores. Global production networks of multinational food companies creating ultra-processed food are supported by high

brand awareness Brand awareness is the extent to which customers are able to recall or recognize a brand under different conditions. Brand awareness is one of the two key components of brand knowledge, as defined by the associative network memory model. It plays ...

, aggressive

globalization Globalization is the process of increasing interdependence and integration among the economies, markets, societies, and cultures of different countries worldwide. This is made possible by the reduction of barriers to international trade, th ...

tactics, and the purchasing of local companies selling similar products. Companies selling ultra-processed food frequently target youth consumers and middle income countries. Many of these companies use

big data Big data primarily refers to data sets that are too large or complex to be dealt with by traditional data processing, data-processing application software, software. Data with many entries (rows) offer greater statistical power, while data with ...

to choose which consumers to market to. Furthermore, the ultra-processed food industry uses indirect and direct lobbying in large countries to influence local

food policy Food policy is the area of public policy concerning how food is produced, processed, distributed, purchased, or provided. Food policies are designed to influence the operation of the food and agriculture system balanced with ensuring human health ...

Affordability for consumers

They often have an extended

shelf life Shelf life is the length of time that a commodity may be stored without becoming unfit for use, consumption, or sale. In other words, it might refer to whether a commodity should no longer be on a pantry shelf (unfit for use), or no longer on a s ...

, an important consideration for lower income consumers without reliable access to refrigeration. Among other reasons for the popularity of ultra-processed foods are the inexpensive cost of their main ingredients. The price of ultra-processed food fluctuated less than unprocessed food over a twelve-year period.

Health effects

The effect of ultra-processed foods on health has mainly been investigated using nutritional epidemiology and so far there has been no

randomized controlled trial A randomized controlled trial (or randomized control trial; RCT) is a form of scientific experiment used to control factors not under direct experimental control. Examples of RCTs are clinical trials that compare the effects of drugs, surgical ...

to investigate the effect of these foods on any health outcome other than weight gain. These studies have shown an overall increased risk for diseaseincluding poor cardiometabolic and

mental health Mental health is often mistakenly equated with the absence of mental illness. However, mental health refers to a person's overall emotional, psychological, and social well-being. It influences how individuals think, feel, and behave, and how t ...

, and reduced life expectancyalthough studies separating different types of ultra-processed food have found adverse effects mainly for only some sub-groups such as

soft drink A soft drink (see #Terminology, § Terminology for other names) is a class of non-alcoholic drink, usually (but not necessarily) Carbonated water, carbonated, and typically including added Sweetness, sweetener. Flavors used to be Natural flav ...

s and animal products, with some sub-groups such as cereals showing an inverse effect. One possible explanation for the adverse effect on health is the presence of contaminants, certain food additives, and the high heat treatment of these foods. Another study proposed that

food addiction A food addiction or eating addiction is any behavioral addiction characterized primarily by the compulsive consumption of Palatability, palatable and Hyperpalatable food, hyperpalatable food items, and potentially also sugar-sweetened beverages (S ...

may also be associated with consumption of ultra-processed foods. There is currently however no scientific consensus. The publicizing of these findings has sparked debate over the categoric

demonization Demonization or demonisation is the reinterpretation of polytheistic deities as evil, lying demons by other religions, generally by the monotheistic and henotheistic ones. The term has since been expanded to refer to any characterization of indivi ...

of ultra-processed foods, with some critics calling for a more balanced view, and others arguing that promoting UPFs could undermine public

health communication Health communication is the study and application of communicating promotional health information, such as in public health campaigns, health education, and between doctors and patients. The purpose of disseminating health information is to inf ...

about their risks.

Environmental impact

In a non-peer-reviewed "comment" article, Seferidi ''et al.'' argue that UPFs require extensive processing and packaging, resulting in higher energy consumption and waste production compared to minimally processed foods. Moreover, the globalized supply chains for the ingredients of ultra-processed foods contribute to greenhouse gas emissions. However, the "UPF" classification also includes plant-based dairy and meat substitutes, which contribute lower emissions compared to their animal-based counterparts. Plant-based UPF-containing diets are not only minimally associated with health risks, but are also linked to lower greenhouse gas emissions and water use. Moreover, studies focusing on the overall food system have consistently found that the greenhouse gas emissions from the supply chain is far outweighed by the emissions from land use and agriculture. Leite ''et al.'' (2022) describes an overlooked aspect of the discourse: UPFs are generally produced from a handful of high-yielding plant species. This phenomenon encourages monoculture and reduces global

agrobiodiversity Agricultural biodiversity or agrobiodiversity is a subset of general biodiversity pertaining to agriculture. It can be defined as "the variety and variability of animals, plants and micro-organisms at the genetic, species and ecosystem levels tha ...

by displacing more diverse traditional foods.

Regulation and policy

Given the health and environmental impacts of ultra-processed foods, there have been calls for better regulation and policy surrounding these products. These measures face significant challenges, including industry opposition and the global nature of food supply chains. Future policy efforts may require a combination of regulation, education, and incentives to promote healthier, more sustainable food choices. Four Latin American countries—Brazil, Uruguay, Peru, and Ecuador—have so far published national official dietary guidelines that recommend avoiding ultra-processed foods.

Chile Chile, officially the Republic of Chile, is a country in western South America. It is the southernmost country in the world and the closest to Antarctica, stretching along a narrow strip of land between the Andes, Andes Mountains and the Paci ...

requires warning labels on some ultra-processed foods and taxes sugar-sweetened beverages. A report on

published by the

World Bank The World Bank is an international financial institution that provides loans and Grant (money), grants to the governments of Least developed countries, low- and Developing country, middle-income countries for the purposes of economic development ...

in 2020 mentions ultra-processed foods as a potential contributor. In 2022, the Scientific Advisory Committee on Nutrition (SACN) reviewed scientific literature to consider whether the British government should adopt a position on ultra-processed food and recommended further research, scheduling a review on its position for June 2024.

Criticism

Following the publication of the Nova classification, some researchers questioned whether food processing should itself be considered a factor in nutrient intake, especially in a prominent 2017 criticism written by researchers, one of which was funded by

Nestlé Nestlé S.A. ( ) is a Swiss multinational food and drink processing conglomerate corporation headquartered in Vevey, Switzerland. It has been the largest publicly held food company in the world, measured by revenue and other metrics, since 20 ...

and the

Kerry Group Kerry Group plc is a public food company headquartered in Ireland. It is quoted on the Dublin ISEQ and London stock exchanges. Given the company's origins in the co-operative movement, farmer-suppliers of the company retain a significant i ...

. UPFs are imprecisely defined and it is unclear how any adverse effects on health may come about. In 2022, Carlos Monteiro and Arne Astrup argued for and against the Nova classification in a series of three articles written in the style of an Oxford debate. Monteiro's 'yes' argument states that the effects of ultra-processed food are demonstrated by representative dietary surveys and long-term

cohort studies A cohort study is a particular form of longitudinal study that samples a cohort (a group of people who share a defining characteristic, typically those who experienced a common event in a selected period, such as birth or graduation), performing ...

; that consuming ultra-processed food is associated with negative health outcomes; and that the associations are supported by discussions of specific mechanisms. Astrup's 'no' argument states that the Nova definition of ultra-processed foods is ambiguous and inherently leads to misclassification of foods; that evidence is lacking for effects that are not already accounted for by known factors such as nutrient composition; that existing evidence is limited to

observational studies In fields such as epidemiology, social sciences, psychology and statistics, an observational study draws inferences from a sample to a population where the independent variable is not under the control of the researcher because of ethical conc ...

rather than being supported by

s; and that some ultra-processing techniques are valuable in achieving the transition to

sustainable food production A sustainable food system is a type of food system that provides healthy food to people and creates sustainable environmental, economic, and social systems that surround food. Sustainable food systems start with the development of sustainable a ...

. The two researchers nonetheless agreed that food processing significantly affects diet quality and health outcomes; that most types of food processing are harmless or beneficial, with a minority being harmful; that some characteristics of food processing are useful for food classification systems; and that further study is required to understand the effect of food processing on human health. A number of studies show that although UPFs in general are associated with higher health risks, there exists a large heterogeneity among UPF subgroups. For example, although bread and cereals are classified as UPFs, a large 2023 study published in ''The Lancet'' finds them inversely associated with cancer and cardiometabolic diseases in the European population (

hazard ratio In survival analysis, the hazard ratio (HR) is the ratio of the hazard rates corresponding to the conditions characterised by two distinct levels of a treatment variable of interest. For example, in a clinical study of a drug, the treated popula ...

0.97). The study found that animal-based products (HR = 1.09) and artificially and sugar-sweetened beverages (HR = 1.09) are most strongly associated with diseases among UPFs. Robinson and Johnstone (2024) cite a similar study conducted in the US population. They argue that there should be a balanced approach in approaching UPFs: consumers should not be prematurely advised to avoid ''all'' UPFs, not just because of physical health concerns (UPF provide a large part of lower-income peoples' nutrition, and replacements may actually be less nutritious), but also because of social costs of the removal of UPFs (unnecessary anxiety and mistrust of science).

References

{{Reflist

External link

''How US Young Adults Understand and Conceptualize Ultra-Processed Foods''
In: Current Developments in Nutrition Volume 8, July 2024 (

Open Access Open access (OA) is a set of principles and a range of practices through which nominally copyrightable publications are delivered to readers free of access charges or other barriers. With open access strictly defined (according to the 2001 de ...

) Food processing Food science Nutrition Food industry Food and drink terminology Health promotion