Consumption of ultra-processed foods and risk of all-cause and cause-specific mortality: the Singapore Chinese health study.

Background: Although higher intake of ultra-processed foods (UPFs) has been associated with a higher risk of mortality in Western populations such as populations from France and the United States (US), evidence in Asian populations remains limited. The aim of this study was to evaluate the association between UPF consumption and the risk of mortality in an Asian population.

Methods: We included 62,197 middle-aged and older Chinese adults who were recruited for the Singapore Chinese Health Study from 1993 to 1998. UPFs were defined from items in the FFQ using the Nova classification, and their consumption was categorized into quintiles according to intake level. Mortality from all-cause, cardiovascular diseases (CVDs), cancer, and respiratory diseases were ascertained via Linkage with a nationwide registry through 2022. Associations between UPF intake and mortality were assessed using Cox proportional hazards regression models.

Results: After 24.9 years (median) of follow-up, 29,472 deaths occurred. In the multivariable-adjusted model (variables related to demographics, anthropometric data, lifestyle factors, medical history, and total energy intake), compared with the lowest quintile of UPF consumption, the highest quintile was associated with higher risks of mortality from all-cause [hazard ratio (HR): 1.06; 95% confidence interval (CI): 1.02-1.10], CVDs (HR: 1.08; 95% CI: 1.01-1.15), and respiratory diseases (HR: 1.10; 95% CI: 1.02-1.19), but not of mortality from cancer (HR: 1.00; 95% CI: 0.94-1.07). The associations remained essentially unchanged after further adjusting for diet quality measured using the Alternative Healthy Eating Index-2010 and antioxidant capacity using the Vitamin C Equivalent Antioxidant Capacity. Among the subgroups of UPFs, positive associations with all-cause mortality were observed for consumption of sweetened beverages (e.g. soft drinks) and sugary products (e.g. crackers and western cakes). This association was stronger in participants who were non-smokers at recruitment [respective HR: 1.08, 95% CI: 1.03-1.13 in non-smokers versus HR: 1.01; 95% CI: 0.94-1.08 in smokers (P for interaction = 0.03)].

Conclusion: Higher intake of UPFs was associated with higher risks of mortality from all-cause, CVDs, and respiratory diseases in an Asian population. These results need to be confirmed in other Asian populations.