Ultra-processed food: what it is and why we’re powerless to control our cravings for it

A fascinating, but frankly horrifying, investigation into our industrialised food system reveals why some scientists refuse to even use the word ‘food’ to describe the things we now cannot stop eating.

Ultra-processed food can’t be replicated in a kitchen. It must come from a chemical factory. Can it therefore honestly be described as food?

The tube of salt and vinegar Pringles was half-full when I pulled it out of the kitchen cupboard. Working at the kitchen table, I munched away mindlessly, until, about 10 minutes later, I realised there was only one crisp left.

It was then that my two-year-old son piped up. “I want one,” he said, looking up from the chaos of plastic toys on the floor. Begrudgingly I handed him the remaining Pringle, which rapidly disappeared.

“’nother one?” he asked. I showed him the empty tube; an almighty tantrum ensued.

The Pringles brand makes a virtue of its moreishness. Its “Once you pop, you can’t stop” slogan was first aired in 1996 and formed the basis of adverts until it was replaced last year. But according to author Chris van Tulleken, this addictiveness is not unique to Pringles. It is in fact a ubiquitous feature of what he calls “ultra-processed food”.

This is the subject of this fascinating, but frankly horrifying, investigation into our industrialised food system. Van Tulleken, an infectious diseases doctor and documentary-maker, digs deep into the science of what he describes as a “new age of eating”.

Ultra-Processed People by Chris van Tulleken

Ultra-processed food is a relatively new term, coined in 2010 by Brazilian scientists, but it has gained traction in recent years among those looking to explain the obesity crisis and the problems with our food industry.

“Processed” food is butter, flour, smoked meat, olive oil – anything that needs a little preparation, but something you could conceivably make in your kitchen with a bit of research and a lot of time. “Ultra-processed” food, on the other hand, is something that you couldn’t even imagine making outside a factory.

One of the scientists van Tulleken speaks to for his book refuses to use the word “food” for these products at all, describing them instead as “industrially produced edible substances”. Take the Pringles my son and I devoured. They are not made from slicing and frying potatoes. Instead they are created from a reformulated potato dough that is forced into metal moulds to form distinctive hyperbolic paraboloid shapes. Water is removed during the frying process and the sparse structure is filled with oil, which provides the “melt-in-the-mouth” texture.

But it is the additives that provide Pringles’ distinctive moreishness. The 22 ingredients listed on the tube include glutamate, guanylate and inosinate. These flavour molecules, where they exist in natural foods, signify to the body that it is about to receive easily digestible protein. “They’re the signature of fermented fish and plants, rich meaty broths, vintage cheese,” van Tulleken writes, a sign “that there is some real nutrition on its way”. But in their synthetic form they trick the body, and when all the stomach receives is a “sad little ball of potato starch . . . we find ourselves reaching for another – searching for that nutrition that never arrived”.

An unhealthy diet of junk food leads quickly to obesity.

On average, people now get 60 per cent of their calories from ultra-processed food. It includes not just the takeaways and ready-to-eat meals they consume in ever-increasing quantities, but also breakfast cereals, the cheap loaves of bread at the supermarket, the ice cream in freezers, the sugar-free yoghurt in fridges.

Not all scientists are convinced that the “ultra-processed” concept is meaningful or useful – or even a problem – and van Tulleken acknowledges that he was also initially sceptical, concerned that it was symptomatic of an “antiscience additive anxiety”. Is the problem, he wondered, not the process of food production itself, but rather the fact that cheaper, industrially produced food tends to be higher in salt, sugar and saturated fat?

However, he became convinced – and he presents a compelling case – that the physical processing and synthetic ingredients used in ultra-processed food hack our appetite and reward system, meaning we crave more food and do not recognise when we are full. He cites evidence that people consume 17 calories more per minute when eating ultra-processed food than an unprocessed diet. “I can inhale a (McDonald’s) burger in well under a minute,” he writes. “And then I’m going to have another because I’m still hungry.”

An employee works at the production site of the Pringles potato chips.

To investigate the effects of such food, for a month he ate an 80 per cent ultra-processed diet. The way he describes this experience is highly concerning (he put on 6kg and brain scans suggested his entire satiety system had been altered) but hugely entertaining. He writes about licking clean the plastic container of his TV dinner, gorging on KFC meals and, while eating lunch with a colleague, “half-wondering if I knew her well enough to ask to finish the food on her plate”.

Like me, he witnessed the impact of such food on his own child, describing his daughter devouring bowl after bowl of Coco Pops. “Her eating wasn’t just mindless: it was trancelike.”

Refreshingly he insists this is not a weight-loss book.

“I don’t have an opinion on the food you should eat,” he writes, warning that all too often such discussions descend into a “quagmire of snobbery”. But he adds: “I feel strongly that to make choices we all need accurate information about the possible risks of our food, and that we should be less exposed to aggressive, often misleading marketing.”

This is an unsettling examination of the food we eat and the industrial system that makes it. I’d promise it will change the way you eat, but I’m already rattling through the cupboard for another packet of Pringles.