As infectious diseases doctor Chris van Tulleken argues in his bestselling book Ultra Processed People, we have entered a new ‘age of eating’ where most of our calories come from an entirely novel set of substances called ultra processed food (UPF) – products which are industrially processed with all manner of additives, and, he says, specifically crafted to be addictive.

In short, UPFs are “not things you have evolved to eat”, van Tulleken asserts, noting they are typically “soft and typically calorie dense, so you eat it at a rate that your body can’t keep up with when it comes to feeling full”.

“Things like protein isolates, refined oils and modified carbohydrates are absorbed so quickly they may not even reach the part of the gut that sends the fullness signal to the brain…”

Common additives in UPFs, particularly emulsifiers and artificial sweeteners, are known to cause harm, he warns.

“Emulsifiers can thin the mucus lining of the gut, allowing faecal bacteria to leak into the blood stream and inflaming your whole body. The non-nutritive sweeteners that tell your body sugar is coming but don’t supply any calories seem to cause metabolic stress and changes to the microbiome.

“Other additives that affect the microbiome are maltodextrins, modified starches and lots of the gums and thickeners. Flavour enhancers (glutamate, guanylate, inosinate and ribonucleotides on ingredient lists) drive excess consumption.

“Again, they tell your body a lie about the nutritional content of the food you’re eating when they’re added out of context,” he writes in the book.

Dr Nina Wilson from Adelaide University says a lack of research makes it difficult to comment on any direct link between the actual industrial processing that’s involved in UPFs and the potential damage this does to the human body.

“There is some talk of perhaps some of the oils that are used, and the way that they’re processed and how that might impact our health and the food product, but I think that’s still quite under-researched at the moment in terms of if there is a clear impact from some of those processes,” she tells EducationHQ.

“I would say it’s more just a combination of the ingredients that are added in, typically some sort of additive or multiple additives, and then using these different processes that we perhaps can’t do in our own kitchen.”

Some 81 per cent of new foods released onto the Australian market in the last decade are considered UPFs. Among products intended for children aged 5-12 years, that figure rose to 93 per cent.

Wilson says children are a target of UPF marketing campaigns for a reason.

“Sadly, I think it’s around how vulnerable children are to marketing when it comes to food and especially younger children, school-aged children.

“[We see companies] putting cartoon characters that they’re familiar with on the front of packaging so that they might choose it…

“But also, we all come from different backgrounds and different socio-economic statuses. And parents may not have a good understanding of the foods available, of ultra-processed foods and what that might mean and how companies market those foods towards children…”

Dr Nina Wilson says emerging research around UPFs' impact on our health needs to be explicitly taught in schools as part of the curriculum. 

In July a group of dieticians called on the Federal Government to urgently make moves to limit unhealthy food marketing to children, arguing this should be a national priority and a ‘central pillar’ of our preventive health agenda.

“This relentless advertising normalises the consumption of highly processed foods and sugary drinks and undermines the efforts of parents, carers, educators and health professionals to support healthy eating habits,” their joint campaign asserts.

“Self-regulation by industry has failed. Voluntary industry codes have not adequately protected children from harmful marketing practices.”

The group say they are deeply concerned that unhealthy diets are driving increasing rates of overweight, obesity and diet-related disease among children and young people, with significant long-term consequences.

Wilson agrees that policy action is needed.

“It’s a huge area, and the marketing is across so many different platforms, but I think there definitely needs to be some sort of policies put in place to restrict what companies are able to advertise to children, absolutely,” she says.

Education around UPFs and their impact on our health also needs to be made more of a focus in the Australian Curriculum, and introduced early on, she adds.

Knowledge is power on this front, she suggests.

“When even younger children have a better understanding of the foods that they eat, when they go to the supermarket with their parents, for example, they reflect on what they’ve learned at school and can kind of help in that decision-making.”

Many UPFs come in packaging that makes health claims, like ‘high in wholegrain fibre’ or ‘full of goodness’ that obscure their full ‘health’ profile.

“I think it’s very clever – to be able to add something into a food to make it seem more healthy or more desirable, and it almost takes away from all the other ingredients that are perhaps in the food that might not be something that we should be consuming a lot of,” Wilson says.

The expert recently tasked her own nutrition and food sciences students with a seemingly elusive task: to make their own Twisties using common supermarket ingredients and everyday household appliances.

The level of industrial processing required to replicate the crispy, aerated snack was soon revealed, she suggests.

“It turns out that it is very, very hard to do, and it’s a very long process as well for the students. I think that’s what they’re most shocked about – that they put so much effort and take so long to create this product that is not even really close to a Twisty when they actually consume it.

“It might almost look similar, but once they actually try it they’re like, ‘oh no, it feels like a different snack altogether’.”

A compelling Canadian study published this year found a link between high consumption of ultra-processed food and increased behavioural and emotional problems in children. 

Speaking on ABC radio, Dr Kozeta Miliku from University of Toronto explained the key findings.   

“...we found that children who consumed more ultra-processed food at the age of three, they tended to have higher behavioural and emotional problems (CORS), by the age of five.

“We also modelled what happens if some of those ultra-processed foods were replaced with minimally-processed foods, things like fruit, vegetables or home prepared meals. We saw that this change was associated with better behavioural scores.”

Internalising behaviours, such as anxiety and withdrawl symptoms, were most strongly associated with UPF consumption, Miliku said. 

Aside from displacing diets rich in nutrients that are important for brain development, the expert said there might be other explanations for the finding.

“So we know about the gut-brain access connection, and ultra-processed foods may also influence the gut microbiome.

“Also potentially the chronic low-grade inflammation may be also part of the pathway, and there is research that shows that ultra-processed foods may promote inflammatory responses, and inflammation has been related earlier with mental and behavioural outcomes,” she said. 

Deakin University research from last year found Victorian children aged between 8 and 12 were getting 47 per cent of their daily energy intake from foods such as cakes, biscuits, pastries, lollies, packaged snacks, sugary drinks and fast food.