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How ultra-processed food took over your shopping basket

Bee Wilson

processed food

What characterises ultra-processed foods is that they are so altered that it can be hard to recognise the underlying ingredients. These are concoctions of concoctions, engineered from ingredients that are already highly refined, such as cheap vegetable oils, flours, whey proteins and sugars, which are then whipped up into something more appetising with the help of industrial additives such as emulsifiers.


See here for many more articles on the issues surrounding processed foods in our diet.

Which foods qualify as ultra-processed? It’s almost easier to say which are not. I got a cup of coffee the other day at a train station cafe and the only snacks for sale that were not ultra-processed were a banana and a packet of nuts. The other options were: a panini made from ultra-processed bread, flavoured crisps, chocolate bars, long-life muffins and sweet wafer biscuits – all ultra-processed.

What characterises ultra-processed foods is that they are so altered that it can be hard to recognise the underlying ingredients. These are concoctions of concoctions, engineered from ingredients that are already highly refined, such as cheap vegetable oils, flours, whey proteins and sugars, which are then whipped up into something more appetising with the help of industrial additives such as emulsifiers.

Ultra-processed foods (or UPF) now account for more than half of all the calories eaten in the UK and US, and other countries are fast catching up. UPFs are now simply part of the flavour of modern life. These foods are convenient, affordable, highly profitable, strongly flavoured, aggressively marketed – and on sale in supermarkets everywhere. The foods themselves may be familiar, yet the term “ultra-processed” is less so. None of the friends I spoke with while writing this piece could recall ever having heard it in daily conversation. But everyone had a pretty good hunch what it meant. One recognised the concept as described by the US food writer Michael Pollan – “edible foodlike substances”.

Some UPFs, such as sliced bread or mass-produced cakes, have been around for many decades, but the percentage of UPFs in the average person’s diet has never been anything like as high as it is today. It would be unusual for most of us to get through the day without consuming at least a few ultra-processed items.

You might say that ultra-processed is just a pompous way to describe many of your normal, everyday pleasures. It could be your morning bowl of Cheerios or your evening pot of flavoured yoghurt. It’s savoury snacks and sweet baked goods. It’s chicken nuggets or vegan hotdogs, as the case may be. It’s the doughnut you buy when you are being indulgent, and the premium protein bar you eat at the gym for a quick energy boost. It’s the long-life almond milk in your coffee and the Diet Coke you drink in the afternoon. Consumed in isolation and moderation, each of these products may be perfectly wholesome. With their long shelf life, ultra-processed foods are designed to be microbiologically safe. The question is what happens to our bodies when UPFs become as prevalent as they are at the moment.

Evidence now suggests that diets heavy in UPFs can cause overeating and obesity. Consumers may blame themselves for overindulging in these foods, but what if it is in the nature of these products to be overeaten?


From a British perspective – where the official NHS Eatwell guide still classifies low-fat margarines and packaged cereals as “healthier” options – it looks extreme to warn consumers off all ultra-processed foods (what, even Heinz tomato soup?). But there is evidence to back up the Brazilian position. Over the past decade, large-scale studies from France, Brazil, the US and Spain have suggested that high consumption of UPFs is associated with higher rates of obesity.

When eaten in large amounts (and it’s hard to eat them any other way) they have also been linked to a whole host of conditions, from depression to asthma to heart disease to gastrointestinal disorders. In 2018, a study from France – following more than 100,000 adults – found that a 10% increase in the proportion of UPFs in someone’s diet led to a higher overall cancer risk. “Ultra-processed” has emerged as the most persuasive new metric for measuring what has gone wrong with modern food.

Why should food processing matter for our health? “Processed food” is a blurry term and for years, the food industry has exploited these blurred lines as a way to defend its additive-laden products. Unless you grow, forage or catch all your own food, almost everything you consume has been processed to some extent. A pint of milk is pasteurised, a pea may be frozen. Cooking is a process. Fermentation is a process. Artisanal, organic kimchi is a processed food, and so is the finest French goat’s cheese. No big deal.

But UPFs are different. They are processed in ways that go far beyond cooking or fermentation, and they may also come plastered with health claims. Even a sugary multi-coloured breakfast cereal may state that it is “a good source of fibre” and “made with whole grains”. Bettina Elias Siegel, the author of Kid Food: The Challenge of Feeding Children in a Highly Processed World, says that in the US, people tend to categorise food in a binary way. There is “junk food” and then there is everything else. For Siegel, “ultra-processed” is a helpful tool for showing new parents that “there’s a huge difference between a cooked carrot and a bag of industrially produced, carrot-flavoured veggie puffs” aimed at toddlers, even if those veggie puffs are cynically marketed as “natural”.

The concept of UPFs was born in the early years of this millennium when a Brazilian scientist called Carlos Monteiro noticed a paradox. People appeared to be buying less sugar, yet obesity and type 2 diabetes were going up. A team of Brazilian nutrition researchers led by Monteiro, based at the university of Sao Paulo, had been tracking the nation’s diet since the 80s, asking households to record the foods they bought. One of the biggest trends to jump out of the data was that, while the amount of sugar and oil people were buying was going down, their sugar consumption was vastly increasing, because of all of the ready-to-eat sugary products that were now available, from packaged cakes to chocolate breakfast cereal, that were easy to eat in large quantities without thinking about it.

To Monteiro, the bag of sugar on the kitchen counter is a healthy sign, not because sugar itself has any goodness in it, but because it belongs to a person who cooks. Monteiro’s data suggested to him that the households who were still buying sugar were also the ones who were still making the old Brazilian dishes such as rice and beans.

Monteiro is a doctor by training, and when you talk to him, he still has the idealistic zeal of someone who wants to prevent human suffering. He had started off in the 70s treating poor people in rural villages, and was startled to see how quickly the problems of under-nutrition were replaced by those of tooth decay and obesity, particularly among children.

When Monteiro looked at the foods that had increased the most in the Brazilian diet – from cookies and sodas to crackers and savoury snacks – what they had in common was that they were all highly processed. Yet he noticed that many of these commonly eaten foods did not even feature in the standard food pyramids of US nutrition guidelines, which show rows of different whole foods according to how much people consume, with rice and wheat at the bottom, then fruits and vegetables, then fish and dairy and so on. These pyramids are based on the assumption that people are still cooking from scratch, as they did in the 50s. “It is time to demolish the pyramid”, wrote Monteiro in 2011.

Once something has been classified, it can be studied. In the 10 years since Monteiro first announced the concept, numerous peer-reviewed studies on UPFs have been published confirming the links he suspected between these foods and higher rates of disease. By giving a collective name to ultra-processed foods for the first time, Monteiro has gone some way to transforming the entire field of public health nutrition.

As he sees it, there are four basic kinds of food, graded by the degree to which they are processed. Taken together, these four groups form what Monteiro calls the Nova system (meaning a new star). The first category – group 1 – are the least processed, and includes anything from a bunch of parsley to a carrot, from a steak to a raisin. A pedant will point out that none of these things are strictly unprocessed by the time they are sold: the carrot is washed, the steak is refrigerated, the raisin is dried. To answer these objections, Monteiro renamed this group “unprocessed and minimally processed foods”.

The second group is called “processed culinary ingredients”. These include butter and salt, sugar and lard, oil and flour – all used in small quantities with group 1 foods to make them more delicious: a pat of butter melting on broccoli, a sprinkling of salt on a piece of fish, a spoonful of sugar in a bowl of strawberries.

Next in the Nova system comes group 3, or “processed foods”. This category consists of foods that have been preserved, pickled, fermented or salted. Examples would be canned tomatoes and pulses, pickles, traditionally made bread (such as sourdough), smoked fish and cured meats. Monteiro notes that when used sparingly, these processed foods can result in “delicious dishes” and nutritionally balanced meals.

The final category, group 4, is unlike any of the others. Group 4 foods tend to consist largely of the sugars, oils and starches from group 2, but instead of being used sparingly to make fresh food more delicious, these ingredients are now transformed through colours, emulsifiers, flavourings and other additives to become more palatable. They contain ingredients unfamiliar to domestic kitchens such as soy protein isolate (in cereal bars or shakes with added protein) and “mechanically separated meat” (turkey hotdogs, sausage rolls).

Group 4 foods differ from other foods not just in substance, but in use. Because they are aggressively promoted and ready-to-eat, these highly profitable items have vast market advantages over the minimally processed foods in group 1. Monteiro and his colleagues have observed from evidence around the world that these group 4 items are liable to “replace freshly made regular meals and dishes, with snacking any time, anywhere”. For Monteiro, there is no doubt that these ultra-processed foods are implicated in obesity as well as a range of non-communicable diseases such as heart disease and type 2 diabetes.

Not everyone in the world of nutrition is convinced by the Nova system of food classification. Some critics of Monteiro have complained that ultra-processed is just another way to describe foods that are sugary or fatty or salty or low in fibre, or all of these at once. If you look at the UPFs that are consumed in the largest quantities, the majority of them take the form of sweet treats or sugary drinks. The question is whether these foods would still be harmful if the levels of sugar and oil could be reduced.


(Read the full article on the Guardian website)