Ultra-processed foods are associated with obesity, cardiovascular disease and other health problems, while controlled research suggests their formulation can also encourage people to eat more calories without intending to.
THE UNIVERSAL RECORD
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Brad Socha | August 10, 2026 | 10:49 AM EST
Ultra-processed food is now a major focus of nutrition research because it describes more than food that has simply been cooked, frozen or packaged. The term generally refers to industrial formulations made from refined food substances and additives, often designed to be convenient, shelf-stable and highly palatable. A growing body of evidence links diets high in these products with poorer health outcomes, although researchers are still working to determine exactly how much of the risk comes from processing itself rather than calories, nutrient quality and the types of foods people choose.
Under the widely used NOVA classification developed by researchers at the University of São Paulo, foods are divided according to the nature, extent and purpose of processing. Ultra-processed products commonly contain ingredients rarely used in home cooking, such as protein isolates, modified starches, certain emulsifiers, flavour enhancers, colours and other additives. Examples can include many soft drinks, packaged snacks, confectionery, sweetened breakfast cereals, processed meat products and ready-to-eat meals.
That does not mean every food that comes in a package is ultra-processed. Frozen vegetables, plain yogurt, canned beans and pasteurized milk can undergo processing while remaining fundamentally different from industrial formulations containing multiple refined ingredients and additives.
Why Ultra-Processed Food May Encourage Overeating
One of the strongest experimental findings comes from a controlled National Institutes of Health study in which 20 adults lived at the NIH Clinical Center and alternated between ultra-processed and unprocessed diets for two weeks each. The diets were designed to offer similar amounts of calories, macronutrients, sugar, sodium and fibre, but participants were allowed to eat as much or as little as they wanted.
Researchers found that participants consumed roughly 500 additional calories per day during the ultra-processed phase. They ate more quickly and gained an average of about 0.9 kilograms, or two pounds, while losing approximately the same amount during the unprocessed phase.
The experiment does not establish that every ultra-processed product has the same effect. It was small and relatively short. But because participants were randomly assigned and closely monitored, it provides stronger evidence for a causal effect on calorie intake and weight than an observational study alone.
Why this happened remains an important research question. Possible explanations include differences in eating speed, energy density, texture, combinations of fat and carbohydrates, and how easily calories can be consumed before the body’s fullness signals catch up. Researchers continue to investigate whether particular additives, changes to the physical structure of food or other characteristics of industrial formulation also contribute.
This distinction matters because processing is not automatically harmful. Cooking, freezing, fermenting and pasteurizing can preserve food, improve safety or increase convenience. The health debate concerns whether certain highly engineered formulations affect eating behaviour and metabolism in ways that cannot be explained solely by their individual nutrients.
What the Evidence Says About Long-Term Health
Large observational studies have repeatedly found that people who consume more ultra-processed food tend to experience higher rates of several adverse health outcomes. A 2024 umbrella review published in The BMJ examined evidence across numerous meta-analyses and found greater exposure was associated with a range of outcomes, with particularly consistent signals involving cardiometabolic health, common mental disorders and mortality.
Other studies have reported associations with obesity, type 2 diabetes, cardiovascular disease and premature death. Research involving more than 266,000 participants in the European Prospective Investigation into Cancer and Nutrition also found higher ultra-processed-food consumption was associated with an increased risk of developing combinations of cancer and cardiometabolic diseases.
These findings should not be interpreted as proof that processing itself caused every observed condition. Most long-term evidence is observational, meaning researchers cannot completely separate ultra-processed-food intake from other factors such as overall diet quality, physical activity, income, smoking or other behaviours.
There is also scientific debate over the classification itself. Some researchers argue that NOVA places nutritionally different foods into the same broad category and does not always identify which specific aspect of processing could cause harm. A 2025 review noted that associations are increasingly consistent for several health outcomes but concluded that uncertainty remains over whether processing independently drives the risk or partly serves as a marker for poor diet quality.
That uncertainty is one reason the World Health Organization is developing specific global guidance on ultra-processed foods. As of August 2026, WHO lists a Guideline Development Group for the subject, reflecting both the growing evidence base and continuing work on definitions, mechanisms and appropriate recommendations.
Canada’s Food Guide already advises people to limit highly processed products, particularly foods and drinks that contribute excess sodium, free sugars or saturated fat. Health Canada emphasizes vegetables and fruits, whole-grain foods and protein foods as the foundation of a healthy eating pattern rather than requiring people to eliminate every processed item.
For consumers, the evidence therefore supports looking beyond a single ingredient or label. A diet dominated by sugary drinks, packaged sweets, salty snacks, processed meats and many ready-to-eat products can provide substantial calories while displacing foods richer in fibre, protein and micronutrients.
What science has not yet established is that all foods classified as ultra-processed carry equal risk, or that processing alone explains every association. The clearest evidence points to the overall dietary pattern: frequent reliance on products that promote high calorie intake and provide poorer nutritional quality is different from occasionally eating a processed food within an otherwise balanced diet.
Understanding that distinction may ultimately prove more useful than treating food processing as a simple dividing line between “good” and “bad.”
Sources:
National Institutes of Health — NIH Study Finds Heavily Processed Foods Cause Overeating and Weight Gain
https://www.nih.gov/news-events/news-releases/nih-study-finds-heavily-processed-foods-cause-overeating-weight-gain
Cell Metabolism / PubMed — Ultra-Processed Diets Cause Excess Calorie Intake and Weight Gain
https://pubmed.ncbi.nlm.nih.gov/31105044/
Food and Agriculture Organization of the United Nations — Ultra-Processed Foods, Diet Quality and Human Health
https://openknowledge.fao.org/handle/20.500.14283/ca5644en
PubMed — Ultra-Processed Foods: What They Are and How to Identify Them
https://pubmed.ncbi.nlm.nih.gov/30744710/
The BMJ / PubMed — Ultra-Processed Food Exposure and Adverse Health Outcomes: Umbrella Review
https://pubmed.ncbi.nlm.nih.gov/38418082/
PubMed — Ultra-Processed Food Consumption and Human Health
https://pubmed.ncbi.nlm.nih.gov/38363072/
International Agency for Research on Cancer — Ultra-Processed Foods and Cancer and Cardiometabolic Multi-morbidity
https://www.iarc.who.int/news-events/ultra-processed-foods-are-associated-with-increased-risk-of-cancer-and-cardiometabolic-multimorbidity/
World Health Organization — Guideline Development Group for Ultra-Processed Foods
https://www.who.int/groups/guideline-development-group-for-ultra-processed-foods
Health Canada — Limit Highly Processed Foods
https://www.canada.ca/en/health-canada/services/food-guide/explore/healthy-eating-recommendations/limit-highly-processed.html
Health Canada — Foods and Beverages That Undermine Healthy Eating
https://www.canada.ca/en/health-canada/services/food-guide/explore/dietary-guidelines/section-2-foods-beverages-that-undermine-healthy-eating.html
About the Author
Brad Socha is the founder of The Universal Record, focused on sourced, factual global reporting. Coverage includes international news, geopolitics, technology, and major developments.