Focus on ultra-processed food (UPF) amongst the nutrition research community is growing apace. In the last three years alone, researchers have suggested links between consumption of UPFs with increased health risks, ranging from the development of cancer to dementia, and increased risk of mortality.
The impact of UPF production on environmental sustainability is another area of concern, with researchers linking increased consumption to higher greenhouse gas emissions.
But some nutritionists and food engineers argue UPFs yield numerous benefits for human and planetary health in the form of safe, nutritious, and environmentally sustainable food for the mass market.
Nutritional benefits of food processing
Food processing is a broad term used to describe change in food as the result of heat, chemistry, or force. In the kitchen, common examples of food processing include boiling potatoes, grating carrots, or using baking powders to make cakes rise in the oven.
Humans have been consuming processed food for more than two million years – beginning with stone tools, rather than today’s steel or aluminium equipment – with obvious nutritional benefits.
“Early examples [of food processing] increased the…availability of nutrients and energy in foods, by cutting off pieces of meat and vegetables to make them easier to eat,” explained Andreas Hakansson, senior lecturer at the department of food technology, engineering and nutrition, from Lund University in Sweden.
Today much of the processing takes place within an industrial setting, but Hakansson argues the practices continues to play a key role in ensuring the availability of nutrients and energy.
“Today, much of what we eat has been industrially processed, even the potatoes I cook at home have gone through a factory to be washed and packaged,” he told press during a briefing on UPFs hosted by trade association FoodDrinkEurope.
The benefits of food processing on the history of public health should not be overlooked, suggested the researcher. Prior to the rapid development of food processing in the secondary industrial revolution, most food consumed was of ‘very poor’ nutritional quality, we were told. “So much of what we do [today] in food processing is to try to make food better.”
The development of milk powder – made using processes such as as boiling, evaporation, and spraying – for example, has proved a ‘gamechanger’ in human nutrition, explained Hakansson. Invented in the 19th century, it allowed for ‘precious proteins’ from skim milk (once cream was removed for butter production) to be saved and fortified. Milk powder, according to the researcher, has proved a ‘very important’ processed food over the years, and is ‘still huge’ in today’s market.
Improved bioavailability and food safety?
Other nutritional benefits associated with UPF can be found in tomato paste developed from raw tomatoes. The crushing, heating, and concentrating processes break down the tomato cell walls, making micronutrients more bioavailable for consumers, explained Edith Feskens, professor of global nutrition at Wageningen University in the Netherlands.
“That is sometimes not well appreciated,” she told press. “Like cooking in the old days…inventing fire and cooking has been helpful in increasing our lifespan and [growing] our brain size. There is archaeological evidence for that.”
And looking to medical nutrition, extreme processing can be ‘lifesaving’, said Gert Meijer, chairman of the European Technology Platform (EPT) Food for Life, and deputy head for corporate regulatory and scientific affairs at food major Nestlé.
In specialised infant formula, processing can serve to break down milk proteins into individual amino acids to facilitate easier digestion. “Without these types of products, I dare say that life would be impossible for those patients or babies. [This is] an emotional example of where I think processing is essential.”
Part of delivering a healthy diet to the mass market means ensuring food safety, which food processing techniques such as sterilization also help provide. This makes food processing ‘beneficial for all stakeholders’, according to EPT Food for Life’s Meijer.
“As a nutritional scientist…it is especially the food safety [element] that is such an important benefit of food processing,” he told media.
Milk, again, offers a good example of improved food safety via processing. In its raw form, milk stays fresh for just a couple of days. If pasteurised and sterilised, that could be extended by a couple of weeks. But in less developed areas with suboptimal transportation and storage conditions, liquid milk can quickly turn sour.
“Think, for example, about Sub-Saharan Africa. If we don’t convert that milk into powder – and arguably that’s an ultra-processed [product] – then we won’t get milk ingredients to consumers.”
The 'green’ question
Throwing sour milk away also results in food waste, which is another reason the experts advocate for some ultra-processing techniques. And not just in developing nations.
Indeed, in developed countries most of food waste occurs in the home. In the Netherlands, where Wageningen University’s Feskens is based, a significant amount of bread, fruits and vegetables are discarded by consumers, she told delegates. But ‘good processing’ can limit the amount of food wasted, and by consequence, its negative impact on the environment.
Lund University’s Hakansson has observed first hand the benefits of extended shelf life on reducing food waste. The researcher opts for vacuum-packed whole grain bread from the supermarket, which is commonly classified an ultra-processed food. “But since it’s vacuum packaged, it keeps for months in my cupboard, so I never have to throw it away.”
Food waste aside, there are other sustainability benefits associated with food processing, according to Hakannsson. UPF margarine, for example, has a significantly lower carbon footprint than artisan made butter. UPF plant-based meat analogues, too, are associated with fewer carbon emissions than conventional meat.
ETP Food for Life’s Meijer goes one step further, arguing that food processing is essential to enable a transition to sustainable food systems, in accordance with the European Farm to Fork strategy.
“We can’t make the transition without food processing. So we need to continue, as a food sector, to continue research into the relationship between food processing and potential impacts on health, but also the environment. There are clear possibilities that by processing food you also increase shelf-life, which can potentially lead to a reduction in food waste.”
But before being able to make ‘very firm’ claims about sustainability benefits of ultra-processing, life cycle assessments will need to be undertaken. These can be ‘expensive’ exercises to undertake, he lamented.
Spotlight on the definition of ultra-processed food
Suggestions that ultra-processed foods could have a more positive impact on the environment than their minimally processed or processed alternatives is at odds with other researchers’ views.
In a study published in The Lancet Planetary Health in 2021, for example, researchers linked UPFs with increased environmental impact. “This study shows for the first time how increasing the consumption of ultra-processed foods has produced more greenhouse gas emissions and used more water and land, even in developing countries like Brazil,” said Dr Ximena Schmidt, co-author and global challenges research fellow at the Centre for Sustainable Energy Use, Brunel University London, at the time.
Similarly, arguments that some UPFs can provide nutritional benefits to consumers do not align with research linking this food category with increased risk of cancer, dementia, or mortality.
So why do nutritionists and food engineers back UPFs to improve food nutrition, safety, and sustainability? They put it down to inconsistencies associated with the most common definition of UPF: categorised by the so-called NOVA food classification system.
Developed in 2009, the NOVA system splits level of food processing into four classifications: from raw and minimally processed foods; to processed culinary ingredients; processed foods; and ultra-processed foods.
The vast majority of research into the UPF category to date – both in terms of nutrition and environmental sustainability - is based on the NOVA system.
But from a food engineering perspective, there is ‘no correlation’ between the foods described as ultra-processed, explained Hakannson, nor those that are ‘intensely processed’. “They are two very different things, and this is an important problem with the scale. From my perspective, as a food engineer, it mixes things up.”
ETP Food for Life’s Meijer also takes issue with NOVA, a classification system he claims has not been ‘scientifically validated’. As does Wageningen University’s Feskens, who argues not all products within the UPF classification are the same. For example, pre-packaged breads offer more nutritional benefits than soft drink, she stressed.
As a result, the nutritionists and food engineer see potential in ultra-processed foods, but not its most used classification scale.
“From my food engineering perspective, there is huge potential in using processing to make food more nutritious and to make it more sustainable,” said Hakansson.
