Ultra-processed foods (UPF) are industrially manufactured food products, generally derived from natural food or synthesized from other organic compounds. The term is commonly associated with the Nova food classification system, which distinguishes UPFs from minimally processed and processed foods. UPFs are typically formulated to be convenient, shelf-stable, and hyperpalatable, often through the use of food additives such as preservatives, emulsifiers, colourings, and flavourings. UPFs typically undergo processes such as moulding, extrusion, hydrogenation, or frying. There is currently no commonly accepted definition of ultra-processed food by codex alimentarius and food regulators such as the European Food Safety Authority.
Ultra-processed foods first became ubiquitous in the global food systems starting in the 1980s, with the term "ultra-processed food" gaining prominence after a 2009 paper by Brazilian researchers as part of the Nova classification system. In the Nova system, UPFs include most industrially produced 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. The category also includes infant formula and food for medicinal purposes. 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. As of 2026, there have been only few clinical trials which provide limited evidence for an adverse health impact of these foods. Epidemiological data suggest that consumption of ultra-processed foods is associated with non-communicable diseases and obesity. A 2024 meta-analysis published in The BMJ 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. Since the 1990s, UPF sales have consistently increased or remained high in most countries. As of 2023, the United States and the United Kingdom lead the consumption rankings, with 58% and 57% of daily calories, 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.
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. Other kinds of researchers have pointed to how ultraprocessed foods have beyond-human impacts, such as increases in food packaging, food waste, and other environmental impacts.
History Concerns about food processing have existed since at least the Industrial Revolution. However, the technical concept of ultra-processed food is more recent, with an origin in the work of Brazilian nutrition researcher Carlos Augusto Monteiro. A 2009 paper by Monteiro and others at the University of São Paulo described the Nova classification system.
In the Nova system, UPFs include most bread and other mass-produced baked goods, frozen pizza, instant noodles, flavoured yogurt, fruit and milk drinks, diet products, baby food, and most of what is considered junk food. 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.
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)
Classification systems
NOVA
Monteiro's team subsequently presented ultra-processed foods as a group in the Nova food classification system. The system focuses on food processing rather than foods types or nutrients. 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, hydrogenated oils, modified starches and protein isolates). Group 1 [un- or minimally processed] foods 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, 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; 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, high-fructose corn syrup, 'fruit juice concentrates', invert sugar, maltodextrin, dextrose and lactose; modified starches; modified oils such as hydrogenated or interesterified oils; and protein sources such as hydrolysed proteins, soy protein isolate, gluten, casein, whey protein and 'mechanically separated meat') 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.
International Agency for Research on Cancer (IARC) The International Agency for Research on Cancer, an intergovernmental agency that forms part of the World Health Organization, 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. 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 defines five levels of food processing: minimally processed, foods processed for preservation, mixtures of combined ingredients, ready-to-eat processed foods, and prepared foods/meals.
NUPENS The Center for Epidemiological Research in Nutrition and Health at the University of São Paulo has proposed a variant on the Nova classification consisting of: unprocessed, minimally, or moderately processed foods; processed foods; and ultra-processed foods.
Identification of ultra-processed foods
Ultra-processed foods cannot be definitely identified by a surface examination of its packaging and food labels, though there are certain characteristics that may indicate an ultra-processed food:
Foods that contain many complex ingredients, especially those that could not be found in a conventional kitchen (e.g. multiple preservatives, emulsifiers, and shelf-life extenders) have higher likelihood to be ultra-processed. Foods that do not have unprocessed or minimally processed ingredients visible may be ultra-processed. Ultra-processed foods are often heavily marketed and come in packaging with nutrition claims like "low-fat," "sugar-free," or "fortified with vitamins."
Health effects Ultra-processed foods tend to be low in dietary fiber and high in calories, salt, added sugar and fat, which are all related to poor health outcomes when eaten excessively. Common examples include packaged snacks, soft drinks, ready meals, and processed meats. They tend to promote overeating and weight gain, largely due to soft texture, high energy density and hyperpalatable nutrient combinations that alter satiety and food-reward.
However, not all ultra-processed foods are unhealthy; some can support a healthy diet, such as whole grain breads, plant milks, yogurts, and jarred pasta sauces, which although highly processed, are nutritious and convenient.
The effect of ultra-processed foods on health has mainly been investigated using nutritional epidemiology, with no adequate clinical research to establish the health effects of these foods, other than weight gain. These studies have shown an overall increased risk for disease – including poor cardiometabolic and mental health, and reduced life expectancy – although studies separating different types of ultra-processed food have found adverse effects only for some subgroups, such as soft drinks and animal products, while other subgroups, such as cereals, showed 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 may also be associated with consumption of ultra-processed foods. A 2026 study published by the Milbank Quarterly journal compared the health impacts and addiction mechanisms of UPFs to cigarettes and called for similar regulations to that of tobacco control. There is currently however no scientific consensus.
The publicizing of these findings has sparked debate over the categoric demonization of ultra-processed foods, with some critics calling for a more balanced view, and others arguing that promoting UPFs could undermine public health communication about their risks.
Obesity and weight gain
Many ultra-processed foods are highly palatable, typically combining high levels of sugar, fat, and salt to enhance flavor and texture, although such combinations are not exclusive to ultra-processed foods. These foods often lack fiber and protein, which are essential for promoting the feeling of fullness and help regulate appetite. Additionally, the high glycemic index of many ultra-processed foods can cause rapid spikes and crashes in blood sugar levels, which further stimulates hunger and overeating. Epidemiological data suggest that consumption of ultra-processed foods is associated with non-communicable diseases and obesity, but this has not been confirmed by RCTs yet. A 2024 meta-analysis published in The BMJ identified 32 studies linking ultra-processed foods (UPFs) to negative health outcomes, though it also noted possible heterogeneity among sub-groups of UPF. The specific mechanisms of the effects were not clear.
Cancer