The complex relationship between diet, quality of life and life expectancy: a narrative review of potential determinants based on data from Italy

Abstract: The increasing life expectancy at birth and the improvement of general health observed worldwide over the previous years are likely due to many factors. In this regard, the Organisation for Economic Cooperation and Development (OECD) has highlighted the favourable situation of the Italian population, which is amongst the most privileged in the world. In Italy, the national healthcare system is easily accessible to the whole population without direct costs, and alcohol abuse and cigarette smoke are less widespread compared to neighbouring countries. Moreover, the population still largely follows a dietary pattern characterised by the consumption of foods rich in protective compounds (plant foods and their components, such as fibre, polyphenols and polyunsaturated fatty acids). According to recent data, a significant consumption of these foods, which are key components of the Mediterranean model, is likely to play a more important role compared to the limited consumption of nutrients considered less favourable (essentially, saturated fat and sugar). Based on these assumptions, it can be inferred that the adoption of coercive legislative interventions—which have been introduced in other western countries to improve diet quality—may not be an optimal strategy in a country like Italy. Such an intervention would contend with psychological and social aspects (namely with the belief that participating in decision-making is an essential right) and with broader indications emerging in the research within this field (the effectiveness of a nudge approach as opposed to constraining interventions). These factors may limit any expected positive impact on health within this context. Level of evidence: Level V, narrative review.