The projections regarding the ageing of the Italian population are cause for great concern; however, the ageing scenario may actually be interpreted in a more optimistic way. Theories formulated in the 80s envisaging a decline of mortality, morbidity and disability in the elderly are now confirmed and prefigure an unexpected decrease in disability rates in the elderly population. The aim of this review is to attempt to explain the reasons for this by analyzing the role played by the various determinants of health, in particular social isolation, which are likely to play an important role in the future as well.