Assessment Metabolic Flexibility in Middle-aged Individuals: The Nutritional Impact of Cheese Consumption

Overview

The aim of the study will be to evaluate the impact of consumption of meat and dairy products from extensive or intensive farming on apparently healthy individuals aged between 45 and 65 years, a stage of life associated with reduced metabolic flexibility and changes in lipid metabolism. The study will analyze: 1. The transcription factor PPAR-α determined by the gene expression of PPAR-α in white blood cells, variations in circulating fatty acid metabolism, and the endocannabinoid system determined by circulating analysis of N-acylethanolamine (NAE), and 2-monoacylglycerols (2-MG); 2. Metabolic flexibility, determined by indirect calorimetry in fasting condition during an incremental exercise; 3. Body composition, determined by bioimpedance analysis, waist circumference, and waist-to-hip ratio.

The study will be a double-blind crossover intervention clinical trial conducted on the aforementioned individuals, who will consume "kent'erbas" cheese products, from extensive and intensive farming. The study will include 105 individuals aged between 45 and 65 years, apparently in good health, recruited from the UTIC cardiology unit of A.O.U.CA Cagliari (Italy). All participants will be provided with a detailed explanation of the study procedures and its purpose, and their participation will be contingent upon signing an informed consent form. Throughout the study, subjects will maintain their regular lifestyle and unrestricted food intake. At the outset of the study, relevant information necessary for an appropriate approach to each participant will be collected, including a comprehensive medical history, measurement of anthropometric parameters, and blood sampling for a thorough hematological, inflammatory, and lipid-metabolomic analysis. In the pecorino study, subjects will consume 350g/week of "kent'erbas" pecorino from extensive farming or 350g/week of "industrial" pecorino from intensive farming for 4 weeks in total. At the end of this period, a blood sample will be taken. Subsequently, there will be a 8 weeks washout period during which participants will follow their usual diet without consuming either type of pecorino. At the end of the washout period, an additional blood sample will be taken. Following this, the participants who had consumed "kent'erbas" pecorino will switch to "industrial" pecorino for 4 weeks, and vice versa. At the end of this second period, a final blood sample will be collected. The quantities of pecorino cheese chosen for intake are representative of the average consumption in Italy.