Evaluation of the bioavailability and cardiometabolic effects of different dosages of coffee phytochemicals. Insights from an innovative acute/chronic intervention study

Coffee consumption is a moment of pleasure for many millions of people but, at the same time, coffee is an important source of bioactive compounds. This Doctoral Thesis reports the main findings of three year of research activity with coffee at its focus. The first part aimed to review the effect of coffee consumption on protection against lipid, protein and DNA damage. Overall, results suggest that coffee consumption can increase glutathione levels and improve protection against DNA damage, especially following regular/repeated intake. The characterization of 65 different capsule-brewed coffees, commercialised by 5 of the most representative brands in Italy, is described in chapter 2. An optimized UHPLC-MS/MS method allowed the detection and quantification of several phytochemicals in one single run and inter-lot and capsule variability was also evaluated for a subset of coffee capsules. Multivariate analysis provided comprehensive information on the phytochemical profile of the different types of coffee, showing a great variability among coffees with some brand-related insights. This study supports the need for an accurate characterization of the espresso coffees when intervention studies have to be designed and conducted for the investigation of the beneficial effects of coffee on human health. The last part of the Thesis describes the study design and the main results of a 3-arm crossover intervention aimed to investigate the bioavailability and beneficial properties of coffee bioactive compounds following coffee consumption at different dosages. In this framework, the contribution of cocoa-based products containing coffee to the pool of circulating metabolites, analysed by UHPLC-MS/MS, has also been considered. The findings of this study described the pharmacokinetic profiles of pyridines, phenolic metabolites and xanthines after the consumption of different coffee dosages. The obtained results allow to increase the knowledge related to coffee bioactives and their role on human health. Besides, they will be a starting point for future studies aimed to better understand the role of coffee on human health.