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Ultra-processed Foods (UPF)
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In one pass To tell whether something is ultra-processed, ask whether a home kitchen could make it: if the ingredient list is full of things no kitchen keeps, it very likely is. Not this — All calories are equal (naïve CICO) — Calories from ultra-processed food and whole food do not behave the same: five mechanisms — reward, hormones, gut microbes, eating speed and food structure — open a real calorie gap between them (Hall 2019).
Educational content, not medical advice — consult a clinician.
design The trial housed 20 adults in a metabolic ward for 2 weeks each of ultra-processed and unprocessed diets, matched for nutrients, eating as much as they wanted.
Sugar, fat and salt, all high at once Mechanism 1 is the pleasure combination (hyperpalatable): many ultra-processed recipes push sugar, fat and salt high at once, which makes it easier to keep eating.
Story path
Chapter 1
Four levels of processing
To tell whether something is ultra-processed, ask whether a home kitchen could make it: if the ingredient list is full of things no kitchen keeps, it very likely is. The NOVA classification ignores calories and nutrients and looks only at the degree of processing.
The four-group system was proposed by Monteiro's team in Brazil in 2009 and is now the classification most used in research on ultra-processed food. Group 1 is food as it comes or only simply handled; group 2 is cooking ingredients such as oil, sugar and salt; group 3 is simple combinations made by traditional methods, such as cheese and traditional bread; group 4 is ultra-processed food, usually with five or more ingredients, many of which a home kitchen never keeps.
Why sort by processing? The same 200 kcal as a chicken breast or as a protein bar is not necessarily the same thing in the body: processing changes a food's structure, how fast it is eaten and how full it leaves you, and counting calories alone cannot see those differences.
The four-group system was proposed by Monteiro's team in Brazil in 2009 and is now the classification most used in research on ultra-processed food. Group 1 is food as it comes or only simply handled; group 2 is cooking ingredients such as oil, sugar and salt; group 3 is simple combinations made by traditional methods, such as cheese and traditional bread; group 4 is ultra-processed food, usually with five or more ingredients, many of which a home kitchen never keeps.
Why sort by processing? The same 200 kcal as a chicken breast or as a protein bar is not necessarily the same thing in the body: processing changes a food's structure, how fast it is eaten and how full it leaves you, and counting calories alone cannot see those differences.
Background · The four groups and intake by country
The NOVA groups in detail (Monteiro 2009). They sort food by degree of processing, not by calories or macronutrients.Group 1 (unprocessed or minimally processed): food as it comes, at most handled for storage or convenience (frozen, dried, cut up): apples, spinach, brown rice, chicken breast, plain yogurt, raw eggs.Group 2 (culinary ingredients): substances taken from group 1 that are not eaten on their own: oil, sugar, salt, flour, butter, vinegar.Group 3 (processed foods): simple combinations of groups 1 and 2, usually two or three ingredients, made by traditional methods such as fermenting, smoking, curing and baking: canned tomatoes, traditional bread (flour, water, yeast and salt), cheese, salted fish, smoked meat, homemade jam.Group 4 (ultra-processed food, ): usually five or more ingredients, often including things a home kitchen simply does not have.
The things a home kitchen does not have fall roughly into these kinds: industrial sugars (high-fructose corn syrup, , and invert sugar); industrial fats (hydrogenated oils, refined palm oil, trans fats); industrial proteins (soy protein isolate, hydrolyzed wheat protein); flavorings and flavor enhancers of every kind; and emulsifiers, thickeners, preservatives, artificial colors and artificial sweeteners (for example polysorbate 80, carrageenan and xanthan gum).
These products are made by industrial extrusion, high heat and pressure, and chemical treatment, with the aim of being hard to stop eating, long-lasting and ready to eat straight from the pack. Soft drinks, instant noodles, breakfast cereals, packaged pastries, sausages, chicken nuggets, ice cream, candy, frozen ready meals and most bagged snacks all belong here.
Quick ways to tell: if the ingredient list includes emulsifiers, thickeners, flavor enhancers, artificial sweeteners, maltodextrin or high-fructose syrup, it is almost certainly ultra-processed; if a home kitchen could not make it, it very likely is; if it has five or more ingredients, it probably is (with a few exceptions: elaborate homemade sauces can also have five or more).
Why sort by processing? The same 200 kcal as a chicken breast or as a protein bar does not necessarily behave the same in the body. The chapter on the Hall 2019 inpatient trial gives the experimental evidence: with nutrients broadly matched, people still ate more on an ultra-processed diet. Counting calories alone cannot explain what processing changes.
How much energy comes from ultra-processed food in different countries: it varies widely. The figures quoted in the Lane 2024 review range, among high-income countries, from about 10% in Italy and about 25% in South Korea to about 42% in Australia and about 58% in the United States; in lower- and middle-income countries, from about 16% in Colombia to about 30% in Mexico. American children and teenagers (ages 2–19) are higher still: in national surveys, the share of their energy from ultra-processed food rose from 61.4% in 1999 to 67.0% in 2018 (Wang 2021).
China's figures use a different ruler: the national data count grams eaten per day, not a percentage of energy. Children and teenagers eat more than adults and their intake is rising faster. In the same national survey (the China Health and Nutrition Survey, CHNS) and under the same NOVA definition, average daily ultra-processed food among 6–18-year-olds rose from 9.7 g in 1997 to 60.0 g in 2011, against 12.0 g → 41.5 g for adults aged 20 and over (Li and Shi). ⚠️ The data stop at 2011, before the wave of delivery apps and milk tea.
Urbanization, two-income households, the spread of food delivery and the industrialization of packaged food have pushed the numbers up together.Frozen dumplings and noodles, packaged snacks, sugary drinks, instant noodles and chain-bakery bread are the main sources.Foods sold on health claims are largely ultra-processed too: low-fat yogurt (with thickeners and sweeteners), protein bars (a long list of additives), whole-grain breakfast cereals (sugar, high-fructose syrup and flavorings).
Why the share matters: the Lane 2024 umbrella review pooled 14 covering about 9.8 million people and found that eating more ultra-processed food was associated with adverse outcomes in 32 of the 45 pooled results. All of this is observational, and for most findings the certainty of evidence is low or very low. The figures for each disease are in the chapter on links to chronic disease.
Eat less of it, but do not go to extremes:
Do not demonize ultra-processed food to the point of never touching a bite; that can feed health anxiety and disordered eating.The goal is to bring the share down clearly, not to reach zero.How: start with one home-cooked meal a week, then several, then most meals; swap things out gradually.Swap sugary drinks, processed meat and packaged snacks first; those three pay off most.
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Chapter 2
Same calories, yet people eat more
With nutrients broadly matched and only the degree of processing changed, people still ate more. In an inpatient crossover trial, people ate about 500 kcal a day more during the two ultra-processed weeks, ate faster, and showed a smaller rise in PYY, a hormone released after meals that damps appetite. Energy expenditure did not differ significantly, so the extra weight came from eating more.
The trial is Hall 2019: 20 adults lived on a metabolic ward at the US National Institutes of Health (NIH), eating an ultra-processed diet for two weeks and an unprocessed diet for two weeks. The two diets as served were matched for calories, macronutrients, sugar, sodium and fiber, and people could eat as much as they liked.
It shows that the problem lies not only in what a food contains but in what it has been turned into: its structure broken down, more energy in each bite, soft and easy to chew, and eaten faster. But with only 20 people and two weeks on each diet, it cannot tell which of those properties matters most.
The trial is Hall 2019: 20 adults lived on a metabolic ward at the US National Institutes of Health (NIH), eating an ultra-processed diet for two weeks and an unprocessed diet for two weeks. The two diets as served were matched for calories, macronutrients, sugar, sodium and fiber, and people could eat as much as they liked.
It shows that the problem lies not only in what a food contains but in what it has been turned into: its structure broken down, more energy in each bite, soft and easy to chew, and eaten faster. But with only 20 people and two weeks on each diet, it cannot tell which of those properties matters most.
Numbers · How the trial worked and what it measured
Hall and colleagues 2019, Cell Metabolism (NIH metabolic ward, N = 20): an inpatient randomized crossover trial. Each person spent two periods of two weeks, one fully ultra-processed and one fully unprocessed, back to back with no gap. The two diets as served were matched for calories, macronutrients, sugar, sodium and fiber, and people could eat as much as they liked. The trial measured body weight, spontaneous food intake, energy expenditure, and hormones involved in hunger and fullness: ghrelin, leptin, and PYY.Results: during the ultra-processed weeks people ate 508 ± 106 kcal a day more (p = 0.0001), the extra coming from carbohydrate and fat, with protein intake the same in both periods; the figure is often rounded to about 500 kcal a day. Weight rose by 0.9 kg on average during the ultra-processed weeks and fell by 0.9 kg during the unprocessed weeks, a swing of 1.8 kg. Total daily energy expenditure did not differ significantly (it was slightly higher in the ultra-processed weeks, without reaching statistical significance), so the extra weight came from eating more. Participants rated the two diets the same for pleasantness and familiarity, and their hunger and fullness ratings did not differ.
Hormones: compared with the ultra-processed weeks, the unprocessed weeks brought higher levels of PYY, which damps appetite after meals; compared with the start of the study, the unprocessed weeks brought lower ghrelin, the hormone that makes you want to eat. The ultra-processed weeks showed neither change.
Later, Hamano 2024 (Japan, randomized crossover, n = 9, one week on each diet) reproduced the same direction with a larger gap, not a smaller one; but with so few people it only shows the direction agrees, and cannot count as stronger evidence.
Why people still ate more when the diets were matched: the trial itself measured only how much people ate, how fast, and a few hormones; it did not isolate the cause. What follows are candidate explanations that do not exclude one another; the first two were raised by the authors themselves.
1. Energy density (calories per gram of food)
The two diets were matched for energy density only when drinks were counted in: 1.024 versus 1.028 kcal/g.Leaving drinks out, the ultra-processed food itself was 1.957 kcal/g and the unprocessed food 1.057 kcal/g, about 85% higher. The authors think this likely contributed to the extra eating.Fiber was matched too (21.3 g versus 20.7 g per 1,000 kcal), partly by adding fiber supplements to drinks on the ultra-processed diet. So this trial did not test the idea that less fiber is the explanation.
2. Eating speed
Ultra-processed meals were eaten faster: 17 ± 1 kcal more per minute, or 7.4 g more per minute by weight (p < 0.0001). That is the difference between the two diets, not the speed on either one.Eating fast means taking in more at a meal before the signals of fullness catch up. Ultra-processed food is soft, easy to chew and needs less chewing, which is one reason it is eaten faster.
3. A broken-down food matrix (not specifically tested in this trial)
In whole foods, fiber, protein, fat and carbohydrate sit together in one structure, so the stomach empties slowly and blood glucose rises gently.Ultra-processing takes these apart and reassembles them: flour plus sugar and whole-wheat bread can carry the same amount of carbohydrate yet differ in how fast the stomach empties and how blood glucose responds.A comparison nutrition teaching often uses: a whole apple, apple juice and apple-flavored gummies have similar calories but behave very differently in the body.
4. Taste and reward
The hyper-palatability of ultra-processed food comes from precisely tuned combinations of sugar, fat, salt and flavorings.Schulte 2015 used the Yale Food Addiction Scale in questionnaire surveys and found that the foods most often linked to addiction-like eating were highly processed ones rich in refined carbohydrate and added fat. This was a questionnaire study, not a measurement of the brain.
5. Emulsifiers and gut bacteria (animal evidence)
In mice, industrial emulsifiers disturbed the gut microbiota and caused gut inflammation and changes resembling metabolic syndrome (Chassaing 2015, Nature). ⚠️ That study tested carboxymethylcellulose (CMC) and polysorbate 80; it did not test carrageenan, which is often named alongside them but is not part of this evidence.Evidence in people is still building.
6. The special place of sugary drinks
Calories in liquid form trigger weaker compensation through fullness than the same calories in solid food (DiMeglio 2000).A 350 ml can of soft drink has about 150 kcal, and dinner does not shrink by 150 kcal to make up for it; most of it becomes extra intake.If you can change only one thing first, drinking fewer sugary drinks is the easiest win.
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Chapter 3
Designed to be hard to stop eating
Ultra-processed food is hard to stop eating not by accident; that is the product's goal.
The bliss point is not the tastiest formula but the one at which people eat the most. A melt-in-the-mouth texture makes food quick to eat, so the calories are already high before the brain registers how much went down. Flavorings, emulsifiers and sweetener blends then tune taste and texture to the limit. For manufacturers these products keep well, ship easily, can be mass-produced, and are profitable.
Laying out these mechanisms is not meant to stop you ever taking a bite. Time, cooking skills, price and relentless marketing all tilt toward ultra-processed food; what you can do is choose within what is realistic for you.
The bliss point is not the tastiest formula but the one at which people eat the most. A melt-in-the-mouth texture makes food quick to eat, so the calories are already high before the brain registers how much went down. Flavorings, emulsifiers and sweetener blends then tune taste and texture to the limit. For manufacturers these products keep well, ship easily, can be mass-produced, and are profitable.
Laying out these mechanisms is not meant to stop you ever taking a bite. Time, cooking skills, price and relentless marketing all tilt toward ultra-processed food; what you can do is choose within what is realistic for you.
Mechanism · How the formulas get people to eat more
The bliss point: in the 1970s and 1980s, the food scientist Howard Moskowitz, working out formulas for drinks and sauces, found that the right ratio of sugar, fat and salt is not simply the stronger the better. There is a point in the middle at which people eat and drink the most. That point is not the tastiest; it is the hardest to stop at. Vlasic pickles, Prego pasta sauce, Dr Pepper and Oreo are examples of the same formulation approach.Hidden energy density: potato chips and corn puffs melt in the mouth, so the brain thinks you have eaten little while the calories are actually high; fast melting makes you swallow quickly, with almost no chewing. The food scientist Steven Witherly described this trick in his book *Why Humans Like Junk Food*. A review pooling how fast foods of different processing levels are eaten found averages of about 35.5 kcal a minute for unprocessed food, 53.7 kcal for processed food and 69.4 kcal for ultra-processed food (Forde 2020). Eating fast makes a meal bigger: a of 22 experiments found that slowing down reduced how much people ate at that meal, although hunger afterwards did not clearly differ (Robinson 2014).
The formulation toolkit also includes flavorings of every kind to build an enticing taste; emulsifiers, thickeners and shortening to recreate a creamy mouthfeel; sweetener blends (including high-fructose syrup) to make sweetness last; and and potassium salts to replace part of the sodium, keeping the salty taste while still allowing a low-sodium label.
Emulsifiers and the reward circuit: the concern about emulsifiers comes from animal experiments. Mice given carboxymethylcellulose and polysorbate 80 developed disturbed gut bacteria, gut inflammation and changes resembling metabolic syndrome (Chassaing 2015); in people it is still under study. On the reward side, in rat experiments both eating and cocaine raised dopamine in the nucleus accumbens, a hub of the brain's reward circuit (Hernandez 1988); a review argues that obesity and addiction overlap in the dopamine circuit, with fewer striatal D2 receptors in people with obesity (Volkow 2008). This is evidence at the level of mechanism and imaging. It shows that too tasty to stop has a basis in the brain; it does not show that ultra-processed food is a drug.
The business case: ultra-processed products keep well, ship easily and can be mass-produced to a standard, and their profit margins are usually higher than those of fresh ingredients. Kearns 2016 used the sugar industry's internal documents to reconstruct a piece of history: in the 1960s the sugar industry funded Harvard researchers whose work steered heart-disease research away from sugar and toward fat. The authors compared such tactics to the tobacco industry's: funding favorable research, diverting attention, moving people back and forth with regulators, and pushing responsibility onto personal choice.
None of this means you must never take a bite. Time, cooking skills, price and relentless marketing all tilt toward ultra-processed food; individual choices still help at the margin. What follows is the situation in China, and how to read packaging.
How China's ultra-processed food industry grew (2000s to 2020s)
Background: McDonald's (1990), KFC (1987) and Coca-Cola (1979) entered China in turn; from the 2000s domestic companies rose, and national brands appeared in instant noodles, bottled drinks, packaged snacks and new-style tea drinks.From the 2010s to now, e-commerce, food delivery and short-video marketing have carried ultra-processed food into smaller cities.
Everyday foods turning ultra-processed:
Instant noodles: invented by Japan's Nissin in 1958 and widespread in China from the 1980s; China is one of the largest markets in the world by consumption.Packaged snacks: spicy duck neck and latiao (konjac strips with plenty of flavorings and seasonings) moved from small workshops to industrial production after the 2010s.Milk tea and sugary drinks: one of the main sources of added sugar in China. ⚠️ We deliberately give no kilograms per person per year figure here: the numbers that circulate online do not match national dietary surveys. Three 24-hour dietary recalls put Chinese adults' average added sugar at about 5 g a day (roughly 1% of energy). Children and teenagers eat more, and their intake is rising, but it is still far below those kilogram-scale claims.Packaged breakfasts: whole-wheat bread, purple-sweet-potato buns, oat bran and high-fiber biscuits; read the ingredient list closely and most are ultra-processed products built on sugar, high-fructose syrup and additives.
Packaging sold on health claims is the most misleading:
0 sucrose: often means high-fructose syrup, maltodextrin and artificial sweeteners have been added; it is still ultra-processed.Low fat: often made up for with sugar and thickeners, which means even more processing.Whole grain: may be a little whole-wheat flour and a lot of refined flour, colored with caramel and malt extract.Protein bars: a long list of additives plus hidden sugar.For children, for pregnancy, for older adults: marketing labels; the products are usually still ultra-processed.
What Chinese families can do:
Cut three categories first for the biggest payoff: sugary drinks, then milk tea, then instant noodles and frozen convenience food.Swap: home-cooked noodles with an egg and a handful of greens, 5 minutes, a complete meal for a few yuan.Breakfast: a boiled egg, milk, a slice of ordinary bread and an apple beat any packaged nutritious breakfast.Snacks: nuts, fruit and plain yogurt (add a little honey yourself if you want sweetness) instead of puffed snacks and packaged pastries.Takeout: hard to avoid entirely; simple dishes (stir-fried, steamed, boiled) bring in fewer ultra-processed ingredients than heavily seasoned ones (numbing-spicy, oily, heavily sauced).
Children are the key group:
The tastes children grow used to often shape their preferences later on, and between ages 6–18 children's intake of ultra-processed food has risen faster than adults'.The cultural expectation that buying snacks for your child is how you show love is the deepest hook in ultra-processed food marketing.The fix: turn it into love shown through time together: cook everyday dishes together, cut fruit together, make dumplings together.
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Chapter 4
Links to chronic disease
People who eat more ultra-processed food tend to have higher risks of several chronic diseases and of early death, and no threshold below which it is clearly safe has been found. All of this comes from observational studies: these are associations, and for most of them the certainty of evidence is low or very low.
The same direction shows up again and again for cardiovascular disease, type 2 diabetes, depression and anxiety, obesity and some cancers, and the associations remain after adjusting as far as possible for obesity, income and exercise. The randomized trials that could show cause and effect have so far measured only short-term food intake (Hall 2019), not disease itself.
For you, bringing down the share of ultra-processed food covers far more ground than chasing any single superfood.
The same direction shows up again and again for cardiovascular disease, type 2 diabetes, depression and anxiety, obesity and some cancers, and the associations remain after adjusting as far as possible for obesity, income and exercise. The randomized trials that could show cause and effect have so far measured only short-term food intake (Hall 2019), not disease itself.
For you, bringing down the share of ultra-processed food covers far more ground than chasing any single superfood.
Evidence · The numbers by disease, and depression
The Lane 2024 umbrella review (BMJ) pooled 45 summary results from 14 covering about 9.8 million people; 32 of them (71%) linked eating more ultra-processed food to worse outcomes. It used two rulers. One grades statistical credibility in five classes (class I convincing, class II highly suggestive, and so on down to class V, no evidence); the other is GRADE certainty of evidence (high, moderate, low, very low). Read the two together:Type 2 diabetes: each extra 10% of energy from ultra-processed food, 1.12; class I, moderate certainty, the most certain finding in the review.Death from cardiovascular disease: highest versus lowest intake, risk ratio 1.50; class I, but very low certainty.Death from all causes: highest versus lowest intake, risk ratio 1.21; class II, low certainty.Depression: risk ratio 1.22; class II, low certainty. Associations were also seen for anxiety and common mental disorders (mostly from cross-sectional studies).Obesity: 1.55, mostly from cross-sectional studies.Cancer overall: risk ratio 1.12, only class III (suggestive).
The authors themselves note that some pooled results show small-study effects or signs of too many significant results, and all-cause death is among them. So these figures show a consistent direction, not precise risks.
Examples from single cohorts: in France's NutriNet-Santé cohort, each extra 10% of ultra-processed food came with a of 1.12 (95% 1.06–1.18) for cancer overall and 1.11 (1.02–1.22) for breast cancer (Fiolet 2018); but once Lane 2024 pooled several studies, the breast cancer association did not hold up (class V). Konieczna 2022 (Spain's PREDIMED-Plus, n = 5,867, older adults with metabolic syndrome): each extra 10% of ultra-processed food over a year came with a fatty liver index 1.6 points higher and a hepatic steatosis index 0.43 higher; these are shifts in continuous indices, not rates of disease. Inflammatory bowel disease: in Lane 2024 the hazard ratio for Crohn's disease was 1.71 but only class IV (weak), and ulcerative colitis showed no association; France's NutriNet-Santé (Vasseur 2020) found no association with inflammatory bowel disease overall, one positive and one null, not two positives. For breathing, the risk ratio for wheezing was 1.40 (class II, low certainty), while the association with asthma itself was not statistically significant.
Lane 2024, Fiolet 2018, Bonaccio 2022 and Srour 2019 found that the associations remained after adjusting as far as possible for obesity, income, education and exercise. But observational studies cannot remove all : people who eat a lot of ultra-processed food often differ in other parts of their lives too.
Traditional Mediterranean eating is built mostly on NOVA groups 1–3. The PREDIMED trial (Estruch 2018, about 7,447 adults at high cardiovascular risk) compared a Mediterranean diet with added extra-virgin olive oil or nuts against advice on a low-fat diet, and major cardiovascular events fell by about 30%. It did not directly reduce ultra-processed food; what it shows is that eating based on whole foods benefits the heart.
The rest of this page is about depression.
Ultra-processed food and depression
Key studies:
Lane 2022 (Nutrients): a meta-analysis of 17 observational studies (n = 385,541; 15 cross-sectional, 2 prospective). The pooled prospective hazard ratio was 1.22 (1.16–1.28) for people eating more versus less ultra-processed food. This is where the widely quoted +22% comes from, not from any .Adjibade 2019 (BMC Medicine, France's NutriNet-Santé, N = 26,000): over an average of 5.4 years of follow-up, each extra 10% of ultra-processed food in the diet came with a hazard ratio of 1.21 (1.15–1.27) for new depressive symptoms. This is an observational association.Jacka 2017, the SMILES trial: a small randomized controlled trial of 67 people over 12 weeks, in adults with moderate to severe depression who were already in usual treatment. The diet group received Mediterranean-style dietary counseling (not specifically aimed at ultra-processed food), and the control group received social support. Depression scores improved clearly more in the diet group. It is one of the first randomized trials in nutritional psychiatry; it is small, and the result needs replicating in larger trials.Lai 2014 (AJCN) is observational evidence, not a randomized controlled trial: it pooled 13 observational studies and found a healthy dietary pattern associated with lower depression risk (odds ratio 0.84), and the authors themselves say they cannot tell which came first.
Possible mechanisms (all still hypotheses):
The gut-brain axis: one idea is that emulsifiers and other additives disturb the gut bacteria and let bacterial endotoxin leak from the gut, causing low-grade inflammation throughout the body, which then affects the brain and changes serotonin (), dopamine and brain-derived neurotrophic factor (BDNF), a protein that supports nerve growth. None of these links has been directly shown in people.Too few micronutrients: ultra-processed food crowds out whole food, so less B vitamins, magnesium, zinc, omega-3 and polyphenols are eaten, which may affect how neurotransmitters are made.Blood glucose swings: ultra-processed foods with a high glycemic index () make blood glucose rise and fall more sharply after meals, and some think this is linked to anxiety and tiredness; the evidence is thin.Adaptation of the reward circuit: repeated intense rewards may make natural rewards such as exercise, sunlight and social contact feel flat. This is inferred from animal and imaging studies and has not been measured directly in people.
In clinical practice:
Some clinicians already discuss dietary patterns alongside treatment for depression, as an add-on.Swapping sugary drinks for water is often treated as the easiest first step.
Important cautions:
Eating less ultra-processed food does not replace antidepressants or psychotherapy; moderate and severe depression still need proper treatment.Improving diet is an add-on.A score of ≥ 10 on the PHQ-9 depression screening questionnaire suggests clinically meaningful depression; see a psychiatrist or mental-health clinic.
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Chapter 5
Which foods to cut first
The surest way to fail at eating less ultra-processed food is to swear you will never touch it again. First see where you actually eat it, then cut the groups that pay off most.
Keep a rough log for a week in four groups: food as it comes, cooking ingredients, simply processed food, and factory-reassembled food. Sugary drinks come first (calories in liquid form do little for fullness), then packaged snacks, then processed meat. Only swaps that take five minutes will stick; zero is not the goal.
If you cannot stop once you start, that is not a failure of willpower. Ultra-processed food is not poison; it is food that has been re-engineered.
Keep a rough log for a week in four groups: food as it comes, cooking ingredients, simply processed food, and factory-reassembled food. Sugary drinks come first (calories in liquid form do little for fullness), then packaged snacks, then processed meat. Only swaps that take five minutes will stick; zero is not the goal.
If you cannot stop once you start, that is not a failure of willpower. Ultra-processed food is not poison; it is food that has been re-engineered.
In practice · Six steps from logging to swaps
Eating it now and then is fine. In observational studies, people who get most of their calories from ultra-processed food year after year have higher risks of several chronic diseases; following that direction, its effects play out over decades. This is a collective, environmental problem that cannot be pinned entirely on personal choice, but choices at the margin do help. This page sells neither panic nor perfectionism; the decision is still yours.How to eat less ultra-processed food: a version you can actually do
Step 1 · See clearly
For one week, write down everything you eat and tag each item N1 (unprocessed), N2 (cooking ingredient), N3 (processed) or N4 (ultra-processed).It does not need to be perfect: an estimate on the order of 60%, 30%, 5%, 5% is enough.You will very likely find more N4 than you expected, and that is an honest place to start.
Step 2 · Cut the three highest-leverage groups first
First: sugary drinks, the single biggest payoff
These include soft drinks, milk tea, juice, flavored coffee and sports drinks.Swap for water, unsweetened tea, black coffee, or soda water with lemon.A cup of milk tea is roughly 300-500 kcal and 30-60 g of sugar; if you drink one a day, cutting it for a week removes 2000-3500 kcal and 200-400 g of sugar.
Second: packaged snacks
These include chips, cookies, candy, factory cakes, high-sugar mass-market chocolate and puffed snacks.Swap for nuts, fruit, plain yogurt, or a square of dark chocolate with ≥ 70% cocoa.
Third: processed meat
This includes sausages, bacon, ham, luncheon meat, fish balls and meat floss.Swap for fresh meat, fish, eggs or legumes.The WHO's International Agency for Research on Cancer (IARC) classifies processed meat as a Group 1 carcinogen; Group 1 means the evidence that it causes cancer is certain, not how large the risk is. By IARC's assessment, each extra 50 g of processed meat a day raises colorectal cancer risk by about 18%.
Step 3 · Three low-cost swaps
Breakfast: packaged cereal with flavored yogurt becomes a boiled egg, milk, oats and a piece of fruit.Takeout lunch: spicy hot pot or Shaxian snack-bar food becomes a simple stir-fry, or steamed rice with one vegetable dish and one meat dish.Frozen dumplings or instant noodles for dinner: fresh noodles with an egg, greens and a few slices of meat instead (5 minutes, < ¥5).
Step 4 · No perfectionism
A target: for example, bring the ultra-processed share down from 50-60% to 20-30%.Getting to zero is unnecessary: birthday cake, the occasional milk tea and holiday snacks are part of quality of life.The 80/20 rule: eat whole foods normally 80% of the time and stay flexible the other 20%; that is what lasts.
Step 5 · Home and the people around you
Do not stock ultra-processed food at home: you will not run downstairs at midnight to buy chips, but you will open the cupboard and take a bag.Agree on a plan with family or housemates: acting together is easier than going it alone.Write your shopping list by NOVA groups 1-3: one big shop at the weekend.Eating out: home-style Chinese beats Western fast food, which beats factory-style milk-tea shops.
Step 6 · When to see a professional
Binge eating or appetite that feels out of control: see a psychologist; this is not a self-discipline problem.Clear obesity together with several metabolic conditions: see a dietitian and an endocrinologist.Depression together with heavy ultra-processed food intake: psychiatry plus nutrition counseling (diet does not replace medication).
In practice · Reading health claims on the package
Health words on a package often signal that the product is ultra-processed: a quick checklistWhen you see these words, read the ingredient list (it is probably ultra-processed):
0 sucrose: check the ingredients; common ones are high-fructose syrup, maltodextrin, artificial sweeteners or fruit-juice concentrate.Low fat, fat-free: check the ingredients; often sugar and thickeners have been added to make up for it, which means more processing.Whole grain: if the first ingredient is not whole-wheat flour or oats but wheat flour with caramel color, the whole grain is fake.Dietary fiber: often processed fiber added separately (inulin, maltodextrin, resistant dextrin), not the food's own fiber.Protein + 6 g, + 10 g: check the protein source; whey isolate and soy isolate mean ultra-processed, milk, eggs and meat do not.For children, for pregnancy, for older adults: marketing labels; the ingredient list is often the same as the adult version.Imported, influencer favorite, anti-inflammatory, detox: marketing words that usually mean a price premium, and the product is mostly ultra-processed.
The 30-second ingredient-list rule:
1. Count the items: 5 or more usually means ultra-processed (home recipes rarely call for 5 or more ingredients of this kind).
2. Look at the first item: the first ingredient is the one present in the largest amount. If it is refined flour, sugar, syrup or high-fructose syrup, be wary.
3. Look for words no home kitchen uses: emulsifier, thickener, flavor enhancer, flavoring, maltodextrin, carrageenan, anti-caking agent, preservative, or a string of food-additive numbers.
4. Check sugar per serving: see how much sugar one serving has (say > 5 g), then think about how many servings you actually eat at once.
5. Check trans fat: 0 g trans fat does not mean none at all; countries allow a product under a certain level to be labeled 0 (in the United States, < 0.5 g per serving). Look for partially hydrogenated oil, shortening or non-dairy creamer in the ingredients.
Common ultra-processed disguises:
| Looks healthy | Actually is |
|---|---|
| Flavored yogurt | Sugar, thickeners, flavorings |
| Instant oatmeal cups | Sugar, syrup, flavorings |
| Whole-wheat cookies | A little whole-wheat flour, lots of refined flour, sugar and oil |
| Vegetable crisps | A dusting of vegetable powder; the rest is factory chips |
| Protein bar | A long list of additives plus hidden sugar |
| Functional drinks | Sugar, caffeine, vitamins (get vitamins from food) |
| Breakfast cereal | Sugar, malt syrup, caramel color, flavorings |
| Premium infant rice cereal | Mostly ground rice plus a marketing premium (most products are fine) |
The single most useful rule: food a home kitchen could make, trust by default; food only a factory could make, look twice by default.
References · 10
- Monteiro, C. A., Cannon, G., Moubarac, J.-C., Levy, R. B., Louzada, M. L. C., & Jaime, P. C. (2018). The UN Decade of Nutrition, the NOVA food classification and the trouble with ultra-processing. Public Health Nutrition, 21(1), 5-17. 10.1017/S1368980017000234
- Monteiro, C. A., Cannon, G., Levy, R. B., Moubarac, J. C., Louzada, M. L. C., Rauber, F., et al. (2019). Ultra-processed foods: what they are and how to identify them. Public Health Nutrition, 22(5), 936-941. 10.1017/S1368980018003762
- Hall, K. D., Ayuketah, A., Brychta, R., Cai, H., Cassimatis, T., Chen, K. Y., et al. (2019). Ultra-processed diets cause excess calorie intake and weight gain: an inpatient randomized controlled trial of ad libitum food intake. Cell Metabolism, 30(1), 67-77.e3. 20 inpatients, 2 weeks per diet, crossover. Meal eating rate was greater on the ultra-processed diet by 17 +/- 1 kcal/min (7.4 +/- 0.9 g/min), p < 0.0001 - that is the between-diet difference; ratings of pleasantness and familiarity did not differ (full text, PMC7946062). Diets were matched for presented calories, energy density including beverages (1.024 vs 1.028 kcal/g), macronutrients, sugar, sodium and fiber (21.3 vs 20.7 g/1000 kcal, partly via fiber supplements added to ultra-processed meals); non-beverage energy density was 1.957 vs 1.057 kcal/g (~85% higher), which the authors say likely contributed. Intake was 508 +/- 106 kcal/day greater on the ultra-processed diet (full text, Table 1 and Results). 10.1016/j.cmet.2019.05.008
- Nestle, M. (2013). Food Politics: How the Food Industry Influences Nutrition and Health (Revised and Expanded 10th Anniversary Edition). University of California Press. www.ucpress.edu/book/9780520275966/food-politics
- Kearns, C. E., Schmidt, L. A., & Glantz, S. A. (2016). Sugar industry and coronary heart disease research: a historical analysis of internal industry documents. JAMA Internal Medicine, 176(11), 1680-1685. 10.1001/jamainternmed.2016.5394
- Lane, M. M., Gamage, E., Du, S., Ashtree, D. N., McGuinness, A. J., Gauci, S., et al. (2024). Ultra-processed food exposure and adverse health outcomes: umbrella review of epidemiological meta-analyses. BMJ, 384, e077310. Umbrella review of 45 pooled analyses (about 9.9 million people): direct associations for 32 (71%) outcomes. Class I (convincing): cardiovascular disease mortality RR 1.50 (1.37-1.63; GRADE very low), type 2 diabetes dose-response RR 1.12 (1.11-1.13; moderate), prevalent anxiety OR 1.48 and common mental disorders OR 1.53 (low). Class II: all-cause mortality RR 1.21 (1.15-1.27; low), heart disease mortality HR 1.66, type 2 diabetes OR 1.40 (very low), depression HR 1.22, adverse sleep outcomes OR 1.41, wheezing RR 1.40 and obesity OR 1.55 (all low). Overall 22 pooled analyses were low quality, 19 very low and 4 moderate; all observational (abstract, PMID 38418082). 10.1136/bmj-2023-077310
- Fiolet, T., Srour, B., Sellem, L., Kesse-Guyot, E., Allès, B., Méjean, C., et al. (2018). Consumption of ultra-processed foods and cancer risk: results from NutriNet-Santé prospective cohort. BMJ, 360, k322. NutriNet-Santé prospective cohort (observational): per 10% more ultra-processed food in the diet, overall cancer HR 1.12 (1.06-1.18; 2228 cases) and breast cancer HR 1.11 (1.02-1.22; 739 cases), still significant after adjusting for markers of diet quality (abstract, PMID 29444771). 10.1136/bmj.k322
- Konieczna, J., Fiol, M., Colom, A., Martínez-González, M. Á., Salas-Salvadó, J., Corella, D., et al. (2022). Does Consumption of Ultra-Processed Foods Matter for Liver Health? Prospective Analysis among Older Adults with Metabolic Syndrome. Nutrients, 14(19), 4142. PREDIMED-Plus, continuous liver-index outcomes, not incident NAFLD risk. No "+30-40%" figure exists in it. 10.3390/nu14194142
- Vasseur, P., Dugelay, E., Benamouzig, R., Savoye, G., Lan, A., Srour, B., et al. (2020). Dietary Patterns, Ultra-processed Food, and the Risk of Inflammatory Bowel Diseases in the NutriNet-Santé Cohort. Inflammatory Bowel Diseases, 27(1), 65-73. A NULL result: neither dietary patterns nor UPF proportion were significantly associated with incident IBD (75 cases in 105,832 participants). It was cited as joint support for a +70-80% risk increase. 10.1093/ibd/izaa018
- Bouvard, V., Loomis, D., Guyton, K. Z., Grosse, Y., Ghissassi, F. E., Benbrahim-Tallaa, L., et al. (2015). Carcinogenicity of consumption of red and processed meat. Lancet Oncology, 16(16), 1599-1600. IARC classifies processed meat as Group 1 carcinogen, red meat as Group 2A. 10.1016/S1470-2045(15)00444-1