In a recent study published in The Lancet Regional Health, researchers investigated the association between ultra-processed food (UPF) consumption and the risk of multimorbidity from cancer, cardiovascular disease, and type 2 diabetes.
Study: Consumption of ultra-processed foods and risk of multimorbidity of cancer and cardiometabolic diseases: a multinational cohort study. Image Credit: Daisy Daisy/Shutterstock.com
Background
In the past two decades, the number of people with multiple chronic diseases has significantly risen, particularly in high-income countries. It is now emerging in low- and middle-income regions.
In Europe, around 50 million people suffer from multimorbidity, defined as having at least two chronic diseases. This condition leads to decreased quality of life, disability, functional decline, and high healthcare costs. Identifying preventable risk factors is essential to mitigate its impact.
The global increase in UPF consumption, constituting 50-60% of daily energy intake in some countries, is alarming. UPFs are industrially manufactured, often as packaged foods like cereals, biscuits, reconstituted meat, instant noodles, and sweetened drinks.
Studies link UPF consumption to higher risks of cardiovascular disease, type 2 diabetes, cancer, and obesity, a potential multimorbidity risk factor. Further research is needed to understand how ultra-processed food consumption contributes to the co-occurrence of major chronic diseases such as cancer, cardiovascular disease, and type 2 diabetes, given their increasing prevalence and shared risk factors.
About the study
Initiated between 1992 and 2000, European Prospective Investigation into Cancer and Nutrition (EPIC) study involved approximately 520,000 participants from 23 centers across 10 European countries.
The study primarily targeted adult volunteers aged 35 to 74 years, and notably, the participant demographics varied across centers; for instance, in Norway, Utrecht, France, and Naples, only women were enrolled, and specific groups such as state-school employees in France and members of local blood donor associations in Italy and Spain were included. The Oxford cohort in the United Kingdom (UK) was distinct, with half of its participants following vegetarian or vegan diets.
For this study, after excluding data from France, Greece, and Norway and removing participants with pre-existing conditions like cancer or cardiovascular diseases, a final cohort of 266,666 participants was formed, consisting of 60% women. Participants underwent regular follow-ups every 3-4 years for major disease updates.
The study's ethical approval came from the International Agency for Research on Cancer (IARC) and Institutional Review Boards of each EPIC center, and participants provided written informed consent.
Their dietary habits in the preceding year were precisely recorded using country-specific food-frequency questionnaires, which were then classified into various food groups. A critical aspect of this classification was using the Nova food classification system to identify UPFs.
The study precisely collected data on the socio-demographic and lifestyle factors of participants, including educational level, smoking status, physical activity, menopausal status, and hormone use. Body mass index (BMI) was calculated using measured height and weight.
To ensure data accuracy, a rigorous approach was taken, including complete case analysis and minimal missing data. The outcomes, like cancer incidence and cardiovascular disease, were verified through cancer registries, medical records, and hospital data.
Sophisticated multivariable Cox proportional hazard models were used for analysis, adjusting for factors such as energy and alcohol intake and physical activity.
The study also conducted detailed subgroup analyses on UPFs and their link to multimorbidity alongside extensive sensitivity analyses. While participants were not involved in setting research questions or outcomes, there were plans to disseminate the results publicly.
Study results
The present comprehensive study analyzed 266,666 participants, 60% of whom were women. The baseline characteristics revealed that women and men consumed, on average 326 g/day and 413 g/day of UPFs, excluding alcoholic drinks, respectively.
This intake represented about one-third of their daily caloric intake. Over a median follow-up period of 11.2 years, 4,461 participants developed multimorbidity involving cancer and cardiometabolic diseases. The most common multimorbidity patterns observed were cancer in individuals with cardiovascular disease, followed by cancer in those with type 2 diabetes, and type 2 diabetes in individuals with cardiovascular disease.
The study's multivariable-adjusted Cox model highlighted a positive association between higher UPF consumption (per 1 standard deviation (SD) increment, roughly 260 g/day) and the risk of developing multimorbidity, even after adjusting for BMI.
These findings were consistent across transitions from baseline to multimorbidity, with similar patterns observed for individual non-communicable diseases (NCDs) like cancer, cardiovascular disease, and type 2 diabetes. The association was particularly strong for type 2 diabetes, although it was slightly attenuated upon further adjustment for BMI.
An in-depth analysis of UPF subgroups revealed that animal-based products and artificially and sugar-sweetened beverages were positively associated with the risk of multimorbidity. Conversely, ultra-processed breads and cereals showed an inverse association, albeit with some uncertainty.
Other UPF subgroups, including sweets, desserts, savory snacks, and ready-to-eat mixed dishes, did not significantly correlate with multimorbidity risk.
The vitality of these findings was confirmed through various sensitivity analyses that included adjustments for different factors, such as the inclusion of ultra-processed alcoholic beverages and animal-based products. Interestingly, the associations observed were somewhat diminished when accounting for soft drink consumption or focusing on the caloric proportion of UPFs in the diet.
These sensitivity analyses underscore the complexity of the relationship between UPF consumption and multimorbidity and highlight the need for a better understanding of dietary impacts on health.
Conclusion
Overall, the study presents a thorough examination of the association between UPF consumption and the risk of multimorbidity, offering valuable insights into the potential health impacts of these foods.
The comprehensive nature of the analysis, including various subgroups and sensitivity tests, contributes significantly to the current understanding of diet-related health risks.
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