An epidemic of overweight/obesity, metabolic syndrome and cardio-metabolic diseases is emerging at

planetary level, and healthy nutrition represents a critical help to counteract this trend. Unfortunately,

simplistic guidelines failed totally or partially, mainly because of the complexity and heterogeneity of nutrition/dietary habits in humans. EURODIET will tackle such complexity and the urgent/unmet need of integrated studies by investigating how the combination of variables usually analyzed separately (ethnicity/geography, sex/gender, socio-economic status/education, previous dietary habits, physical activity and smoking) affects adoption of healthy dietary habits and conventional as well as novel metabolic and inflammatory biomarkers in a large number of subjects spanning from 50 to 79 years of age. This approach is feasible being EURODIET a multidisciplinary consortium having access to existing datasets/biological samples of large European projects SHARE and NU-AGE. EURODIET  will: i) integrate existing cohorts and collect new ad hoc data (e.g. omics-based biomarker identification); ii) perform a follow-up study on dietary habits, health status and incident diseases on a subsample of subjects based on existing data collected at two time points within the NU-AGE project; iii) perform two proof-of-concept randomized controlled trials to assess the effects of adherence to a healthy a whole-diet approach in adults with and without metabolic disease; iv) determine facilitators and barriers for adherence to healthy dietary patterns; v) bridge the gap between academic research, public health practice and the food production industry; vi) provide state-of-the-art training to young scientists focusing on the importance of addressing/combining biological and non-biological variables in dietary interventions and metabolic diseases.

The exploration of the true impact of dietary patterns on important metabolic and inflammatory biomarkers that impinge on metabolic abnormalities should encompass interactions between biological (e.g. body composition, gender and age), behavioural (e.g. physical activity and smoking) and socio-demographic (e.g. education, income, place of residence) variables. 

In this context, EURODIET has generated new data evidencing the beneficial impact of mediteranean diet on the occurrence of chronic diseases in older European adults after adjutments with several socio-demographic factors and provided in depth-knowledge on the role of fat subtypes and protein amount and source on skeletal muscle, an important metabolic organ. Further experimental work is warranted in order to elucidate the mechanisms underpinning the action of dietary fibre on the regulation of muscle mass. 

Using isocaloric substitution modelling, a reduced sarcopenia risk was observed when increasing plant protein to the detriment of animal protein, while holding total protein intake constant. Further, this result remained significant after stratifying the analysis by adherence to different levels of protein intake. Our findings suggest that older adults may benefit from increasing protein intakes above current recommendations. Besides total amount, protein source should be considered when promoting health dietary habits in older adults for the prevention of sarcopenia.

 Finally, a reduction of saturated fatty acids for the benefit of polyunsaturated fatty acids is associated with a lower sarcopenia risk, particularly in those with a protein intake below current guidelines, irrespective of age, smoking habits, metabolic disturbances, and adherence to physical activity guidelines.