Consumo de alimentos ultraprocessados e interleucina-6 sérica na vida adulta

Abstract

Interleukin-6 (IL-6) presents a causal relationship with cardiovascular diseases, which are the main cause of morbidity and mortality worldwide. One of the most important behavioural risk factors of cardiovascular diseases is an unhealthy diet, and the consumption of ultra-processed foods has been observed among several populations worldwide. Besides, there is a growing body of evidence on the relationship between consumption of ultra-processed foods and damage to health. Therefore, the first article of this thesis aimed to review the literature to understand the relationship between food processing and cardiometabolic risk factors. It was concluded that the consumption of ultra-processed foods may increase the risk for obesity among adults, with moderate level of evidence. In the second article, socioeconomic and behavioural factors associated with the serum concentration of IL-6 at 30 years of age were investigated, using data from 2809 participants of the 1982 Pelotas Birth Cohort. Among men, low education and smoking were associated with serum IL-6, while African ancestry and lower-income were associated with the highest concentrations of this inflammatory biomarker among women. Also, physical activity showed an inverse relationship with mean IL-6 among women. In both sexes, adiposity was the main predictor of serum concentrations of this biomarker. Finally, the third article of this Ph.D. thesis aimed to evaluate longitudinally the association between consumption of ultra-processed foods and chronic inflammation, measured by serum IL-6, and to investigate the mediating role of adiposity in this association. We analysed two cohort studies data from Portugal (n = 524) and Brazil (n = 2888). Females from the EPITeen belonging to the third (2.20 pg/mL; 95% CI 1.60; 3.01) and fourth (2,64 pg/mL; 95% CI 1.89; 3.69) quartiles of UPF consumption had higher mean IL-6 compared to those from the first quartile (1.31 pg/mL; 95% CI 0.95; 1.82). In Pelotas, males who were within the third (1.50 pg/mL; 95% CI 1.41; 1.59) and fourth (1.59 pg/mL; 95% CI 1.49; 1.70) quartiles of UPF consumption had higher means of IL-6 than those from the first (1.40 pg/mL; 95% CI 1.32; 1.49). The p-value of linear trend was significant (< 0.01) in both findings. Furthermore, there was no statistical evidence that adiposity is a mediator of the relationship between ultra-processed foods and interleukin-6.