A recent study has found no link between ultra-processed foods (UPFs) – including bread and cereal – and an increased risk of suffering a combination of diseases, like cancer and diabetes. In fact, the experts suggested there was a reduced risk for people eating bread and cereal, which could be attributed to their fibre content.
On the other hand, there was more risk of poorer health if people consumed lots of artificially sweetened or sugary drinks, or animal-based UPFs like processed meat, said the researchers.
The scientists involved in the large study included several from the International Agency for Research on Cancer, the specialised cancer agency of the WHO, reports The Independent.
UPFs are foods that usually contain ingredients that people would not add when they were cooking homemade food, like chemicals, colourings, sweeteners and preservatives.
The aim of the latest study was to investigate the link between UPFs and the risk of people suffering at least two chronic diseases at once from a list of cancer, cardiovascular disease and type 2 diabetes.
Experts included consideration of the Nova food classification system containing more than 11 000 food items.
The study included 266 666 people from seven European countries, 60% of whom were women.
Those in the study had a 12-month food intake assessed through food frequency questionnaires, with the results showing the mean average UPF intake for men and women was 413g/day and 326g/day respectively.
This equated to 34% of a man’s daily calories coming from UPFs and 32% of a woman’s.
After a typical follow-up of 11.2 years, a total of 4 461 people had developed both cancer and cardiovascular disease or diabetes.
Analysis showed that those who consumed higher amounts of UPFs had a 9% increased risk of suffering two illnesses.
But when researchers looked at subgroups of UPFs, they said the link was most notable for animal-based UPFs and artificially and sugar-sweetened beverages.
Other sub-groups, such as ultra-processed breads and cereals or plant-based alternatives, were not associated with risk.
The researchers said their study “provides evidence of a differential relationship of subgroups of ultra-processed foods”.
“Artificially and sugar-sweetened beverages, animal-based products and sauces, spreads and condiments, but not other subgroups, were associated with increased risk, suggesting that more nuanced subgroup analyses of ultra-processed foods are warranted.”
Statistical analysis even indicated there may be a reduced risk for people eating bread and cereal, which the researchers suggested could be down to their fibre content.
Reynalda Cordova, who led the study and works at both IARC and the University of Vienna, said that for each 260g increased intake in UPF, the risk of suffering two diseases – comorbidity – rose by 9%.
“With each average portion of UPF per day, the risk increases by 9%,” she said.
“The risk is higher for a person who eats many portions of UPFs daily than for a person who eats very little.”
Heinz Freisling, co-author, and study lead at IARC, said the study “emphasises that it is not necessary to completely avoid ultra-processed foods; rather, their consumption should be limited, and preference be given to fresh or minimally processed foods”.
Dr Helen Croker, assistant director of research and policy at the World Cancer Research Fund, which helped fund the study, said:
“What is particularly significant … is that eating more ultra-processed foods, in particular animal products and sweetened beverages, was linked to an increased risk of developing cancer along with another disease such as a stroke or diabetes.
“Our cancer prevention recommendations include limiting processed foods high in fat, starches or sugars, avoiding processed meat and eating plenty of wholegrains, vegetables, pulses and fruits.”
Dr Ian Johnson, nutrition researcher and emeritus fellow at the Quadram Institute, a centre for food and health research, said the researchers recognised “that the definition of UPF covers a very broad and diverse range of foods”.
“They therefore broke the classification of UPF down into subdivisions and explored the contributions of the various different food types to the risk of developing multimorbidity,” he said.
“However, a wide range of other products, including ready-to-eat dishes, savoury snacks, and sweets and desserts, were not shown to be associated with increased risk.
“Importantly, ultra-processed bread and cereal products showed an association with a reduction in risk.
“These observations suggest a role for some UPF in the onset of multiple chronic disease, but they also show that the common assumption that all UPF foods are linked to adverse health effects is probably wrong.
“Furthermore, ultra-processed cereal products may be beneficial to health, perhaps because some provide convenient and palatable sources of dietary fibre.”
Study details
Consumption of ultra-processed foods and risk of multimorbidity of cancer and cardiometabolic diseases: a multinational cohort study
Reynalda Cordova,Vivian Viallon, Emma Fontvieille, Laia Peruchet-Noray, Anna Jansana, Karl-Heinz Wagner, et al.
Published in The Lancet Regional Health Europe on 13 November 2023
Summary
Background
It is currently unknown whether ultra-processed foods (UPFs) consumption is associated with a higher incidence of multimorbidity. We examined the relationship of total and subgroup consumption of UPFs with the risk of multimorbidity defined as the co-occurrence of at least two chronic diseases in an individual among first cancer at any site, cardiovascular disease, and type 2 diabetes.
Methods
This was a prospective cohort study including 266,666 participants (60% women) free of cancer, cardiovascular disease, and type 2 diabetes at recruitment from seven European countries in the European Prospective Investigation into Cancer and Nutrition (EPIC) study. Foods and drinks consumed over the previous 12 months were assessed at baseline by food-frequency questionnaires and classified according to their degree of processing using Nova classification. We used multistate modelling based on Cox regression to estimate cause-specific hazard ratios (HR) and their 95% confidence intervals (CI) for associations of total and subgroups of UPFs with the risk of multimorbidity of cancer and cardiometabolic diseases.
Findings
After a median of 11.2 years of follow-up, 4461 participants (39% women) developed multimorbidity of cancer and cardiometabolic diseases. Higher UPF consumption (per 1 standard deviation increment, ∼260 g/day without alcoholic drinks) was associated with an increased risk of multimorbidity of cancer and cardiometabolic diseases (HR: 1.09, 95% CI: 1.05, 1.12). Among UPF subgroups, associations were most notable for animal-based products (HR: 1.09, 95% CI: 1.05, 1.12), and artificially and sugar-sweetened beverages (HR: 1.09, 95% CI: 1.06, 1.12). Other subgroups such as ultra-processed breads and cereals (HR: 0.97, 95% CI: 0.94, 1.00) or plant-based alternatives (HR: 0.97, 95% CI: 0.91, 1.02) were not associated with risk.
Interpretation
Our findings suggest that higher consumption of UPFs increases the risk of cancer and cardiometabolic multimorbidity.
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