High consumption of ultra-processed foods (UPFs) may be associated with an increased risk of premature death, according to a multinational study.
The analysis, published in the American Journal of Preventive Medicine, included data from eight countries including the UK and US and examined the potential health impacts of UPFs, which are becoming increasingly prevalent in global diets.
UPFs include items such as processed meats, fizzy drinks, biscuits, ice cream, and some breakfast cereals.
These products typically contain more than five ingredients—many of which are not used in home cooking—such as artificial sweeteners, preservatives, and emulsifiers designed to improve flavour, texture, or shelf life.
Researchers analysed dietary survey data and national mortality statistics from Australia, Brazil, Canada, Chile, Colombia, Mexico, the UK, and the US.
They estimated that in countries where UPFs make up over half of daily calorie intake, such as the UK and US, 14% of early deaths could be attributed to these foods.
In countries with lower UPF consumption—less than 20% of total calories—like Brazil and Colombia, the figure was estimated at around 4%.
Dr Eduardo Nilson, lead author from Brazil, explained that UPFs may affect health “because of the changes in the foods during industrial processing and the use of artificial ingredients, including colourants, artificial flavours and sweeteners, emulsifiers, and many other additives and processing aids”.
Based on their modelling, the study estimated that in 2018, there were 124,000 premature deaths in the US linked to UPFs, and nearly 18,000 in the UK.
However, the study could not prove a causal relationship. The amount of UPFs in a person’s diet is often tied to other factors such as physical activity, socioeconomic status, and overall dietary habits—all of which influence health.
Professor Kevin McConway, emeritus professor of applied statistics at the Open University, warned of the limitations of the study: “It’s still far from clear whether consumption of just any UPF at all is bad for health, or what aspect of UPFs might be involved. This all means that it’s impossible for any one study to be sure whether differences in mortality between people who consume different UPF amounts are actually caused by differences in their UPF consumption. You still can’t be sure from any study of this kind exactly what’s causing what.”
Dr Nerys Astbury, an expert in diet and obesity at the University of Oxford, also noted: “Many UPF tend to be high in these nutrients,” referring to fat and sugar. She added that the evidence does not yet confirm whether UPFs themselves are harmful beyond their nutritional content.
Dr Stephen Burgess of Cambridge University said, “Ultra-processed foods may be more than a bystander,” despite the difficulty of proving direct harm. The Food and Drink Federation argued the term ‘ultra-processed food’ unfairly “demonises a wide variety of food” and emphasised that all additives used in manufacturing are approved by the Food Standards Agency.
Conor Seery