Greater Ultra-Processed Food Intake Tied to Higher Mortality Risk

In a recent publication in BMJ, scholars delved into the correlation between ultra-processed food (UPF) consumption and overall and specific causes of mortality in the United States (US).

Background: Ultra-processed foods, characterized by their low-quality, high-energy density, and industrial preparation, dominate the food landscape in affluent nations and are increasingly prevalent in middle-income countries.

These items often contain added sugars, salt, saturated fats, trans fats, processed carbohydrates, and minimal fiber, along with potentially harmful additives and contaminants.

Extensive cohort studies indicate that ultra-processed foods have adverse health effects, including obesity, cardiovascular disease, type 2 diabetes, colon cancer, metabolic syndrome, depression, postmenopausal breast cancer, and increased overall mortality.

However, there is limited research on the impact of UPF consumption on mortality outcomes, emphasizing the need for robust evidence to guide dietary recommendations and inform food policy.

About the Study: In this population-based cohort study, researchers explored whether UPF consumption is associated with increased overall mortality or mortality from specific causes, particularly cancer.

The investigation focused on female participants from the Nurses’ Health Study (NHS, 1984–2018) aged 30-55 years and male participants from the Health Professionals Follow-up Study (HPFS, 1986–2018) aged 40–75 years.

The study encompassed 74,563 females and 39,501 males without a history of cardiovascular disease, diabetes, or cancer, excluding those with implausible calorie intakes or missing UPF intake data.

Participants provided lifestyle and medical history information through regular questionnaires, while UPF intake was assessed using the NOVA classification and food frequency questionnaires. Dietary quality was evaluated using the Alternative Healthy Eating Index-2010 (AHEI) scores.

Follow-up duration ranged from the questionnaire return date to death or the end of the follow-up period (June 30, 2018, for NHS and January 31, 2018, for HPFS), whichever came first.

Deaths were reported by offspring or identified through national records, with causes determined using International Classification of Diseases, eighth revision (ICD-8) codes.

Multivariate Cox proportional hazards regression modeling was employed to analyze the relationship between UPF intake and overall and cause-specific mortality, adjusting for various covariates.

Results: Over median follow-up periods of 31 and 34 years for males and females, respectively, 48,193 deaths were recorded, including 18,005 males and 30,188 females.

Stratifying by cause, a considerable number of deaths were attributed to cancer, cardiovascular disease, respiratory issues, and neurodegenerative conditions.

Individuals with higher UPF intake tended to be younger, less physically active, and had higher body mass index values, lower AHEI scores, and higher smoking rates.

Compared to those with lower UPF intake, individuals with higher intake levels demonstrated a slight increase in overall mortality, particularly deaths unrelated to cardiovascular disease and cancer.

Specific types of ultra-processed foods, such as meat, seafood, and poultry-based products, as well as artificially and sugar-sweetened beverages, dairy desserts, and breakfast items, were associated with elevated mortality rates.

However, the relationship between UPF intake and mortality varied across different levels of dietary quality, with improved diet quality consistently linked to lower mortality risk.

In conclusion, greater consumption of ultra-processed foods is linked to a slight rise in overall mortality, primarily driven by certain food categories. Thus, prudent use of UPFs is advised for long-term health, with emphasis placed on dietary quality as a more significant determinant of mortality. Further research is warranted to validate these findings across diverse populations.

For more information: Association of ultra-processed food consumption with all-cause and cause-specific mortality: population based cohort study, BMJ, https://doi.org/10.1136/bmj-2023-078476