A recent study published in the journal Clinical Nutrition highlights significant concerns regarding ultra-processed foods (UPFs) and their impact on health and longevity. Conducted with a large cohort of 27,670 participants, this long-term study utilized plasma metabolite analyses and hazard models to evaluate the associations between UPF intake and mortality risk over an impressive follow-up period of 23.3 years.
The findings reveal a troubling link between UPF consumption and an increased risk of all-cause mortality, particularly among females. Researchers found that higher UPF intake was associated with heightened risks of cardiovascular disease (CVD) mortality, premature death, and respiratory disease mortality. However, there was no significant association found with cancer mortality. Furthermore, plasma metabolite analyses revealed 93 metabolite signatures correlated with increased all-cause mortality risk.
Understanding Ultra-Processed Foods
Ultra-processed foods are defined by the NOVA classification system as food products that undergo extensive transformation and include multiple ingredients, such as additives and processed raw materials, while offering little nutritional value. Despite their low cost, convenience, and appealing taste, these foods have raised alarm among public health experts due to their rising popularity over recent decades.
In Western countries and developed regions, UPFs have become a significant part of the diet, accounting for 14-44% of Europeans’ daily intake and nearly 60% of the American diet. As the consumption of these foods has soared, so have concerns regarding chronic health issues associated with their intake. A growing body of observational evidence has linked increased UPF consumption with serious health risks, prompting organizations like the World Health Organization (WHO) and the Centers for Disease Control and Prevention (CDC) to recommend limiting their intake.
The Study’s Design and Methodology
This comprehensive study aimed to investigate the relationship between UPF consumption and various mortality outcomes, including all-cause mortality, premature death, CVD mortality, and respiratory disease mortality. It sought to address limitations found in previous research, such as small sample sizes and a narrow racial focus, by leveraging data from the Malmö Diet and Cancer (MDC) cohort study.
The MDC study initially included over 74,000 Swedish citizens aged 45 to 73, with 30,446 individuals participating in the baseline screening. After excluding participants with incomplete dietary records, the final cohort consisted of 27,670 individuals. To gather data on dietary UPF intake, participants completed a custom 168-item questionnaire along with an hour-long nutritional interview.
Plasma metabolite analyses were conducted using untargeted liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS), allowing researchers to explore the complex relationships between diet and health. Mortality outcomes were tracked using records from the National Board of Health and Welfare, the Statistics in Sweden, and the Swedish National Tax Agency.
Key Findings
Among the 27,670 participants, 60.7% were female, with an average age of 58.1 years. During the follow-up period, approximately 41% of participants (11,333 individuals) died from chronic diseases, including 3,938 from cancer, 3,709 from CVD, and 758 from respiratory diseases. Notably, 3,672 of these deaths were classified as premature, occurring before the age of 75.
The study found that UPFs constituted 13.4% of the participants’ total food intake. Those who consumed higher amounts of UPFs were typically older, more likely to be female, and less likely to smoke or consume alcohol. Additionally, higher UPF intake was associated with a lower level of education, increased body mass index (BMI), and higher cancer prevalence. The primary contributors to UPF intake included breakfast cereals (26%), beverages (23.3%), sugary products (18.4%), sauces (15.5%), and meat and fish (13.6%).
Hazard Ratio Analyses
The analysis of hazard ratios (HRs) demonstrated significant, nonlinear positive associations between UPF consumption and all-cause mortality (Pnonlinear = 0.022). In females, this association was notably stronger and linear, while in males, it exhibited a weaker, J-shaped curve. The HRs for all-cause mortality, premature mortality, CVD-related deaths, and respiratory diseases were recorded at 1.06, 1.06, 1.05, and 1.08, respectively. Surprisingly, no significant correlation between UPF consumption and cancer mortality risk was identified.
In the metabolomic analysis, over 900 metabolites were identified, with 93 significantly associated with UPF intake and linked to a 23% increase in mortality risk (HR = 1.23). Conversely, the consumption of minimally processed and processed foods was associated with a reduction in mortality risk (HR = 0.87), indicating a 13% decrease in risk.
Implications for Public Health
This groundbreaking study provides the first empirical evidence linking long-term UPF consumption with increased mortality risk. The findings indicate that females and older individuals face a heightened risk compared to younger individuals and males. Those with higher BMIs and individuals who have never smoked are also at an increased risk.
Additionally, lipid and lipoprotein analyses supported these conclusions, showing that higher UPF intake correlates with unfavorable lipid profiles, including lower levels of high-density lipoprotein (HDL) and higher levels of very-low-density lipoprotein (VLDL). The identification of 93 metabolic signatures related to UPF exposure offers a valuable tool for future research in quantifying physiological impacts.
These findings strengthen the case for global public health campaigns aimed at reducing UPF consumption. By raising awareness about the potential health risks associated with these foods, the study encourages consumers to reconsider their dietary choices for better health outcomes.