Abstract
Background and Objectives
High ultra-processed food (UPF) consumption has been associated with chronic low-grade inflammation, potentially related to the progression and prognosis of breast cancer. We aimed to evaluate the association between UPF consumption and one-year changes in serum levels of pro-inflammatory cytokines (IL-6, IL-18, and TNF-α).
Methods
Analysis included a sub-cohort (n = 176) of the LifeBreast project, a multicenter randomized trial investigating whether a Mediterranean Diet (MedDiet) vs. a low-fat diet (control) affects the prognosis among breast cancer patients. Dietary intake was assessed through a 149-item food frequency questionnaire, with UPF identification based on the NOVA classification. Participants were categorized into tertiles of UPF intake. Cytokine concentrations were measured using the Olink® Target 48 kit. The primary outcome was the change in cytokine levels from baseline to one-year, estimated using multivariable linear regression models.
Results
A significant linear association was found between higher UPF intake and increased TNF-α levels (ptrend=0.032). In stratified analyses, this association was notably stronger within the control group (ptrend=0.001). Although not statistically significant, regression coefficients for both IL-6 (bT3=0.11; 95% CI: -1.49 to 1.71) and IL-18 (bT3=13.32; 95% CI: -43.47 to 70.10) suggested higher levels in the highest UPF tertiles. Notably, these trends were more pronounced among participants allocated to the control group compared to the MedDiet (IL-6: bT3=0.85 vs. −0.57; IL-18: bT3=47.60 vs. −23.81).
Conclusions
Higher UPF intake was associated with a linear increase in TNF-α levels, particularly among participants not following the MedDiet. Non-significant upward trends for IL-6 and IL-18 were most pronounced in the low-fat group, suggesting that adherence to the MedDiet may mitigate UPF-induced pro-inflammatory effects in breast cancer survivors.
Key messages
• UPFs Drive Inflammation: High ultra-processed food intake linearly increases TNF-α levels over time, promoting chronic low-grade inflammation in breast cancer survivors.
• MedDiet as a Buffer: Adherence to a Mediterranean Diet may mitigate the pro-inflammatory effects of UPFs, whereas low-fat diets show a stronger inflammatory response.