Analysis of prospective data collected between 1984 and 2008 by the CERN medical team (European Centre of Nuclear Research, Geneva) concerning 2040 former employees who were retired or had died stimulated our interest on the impact of inequalities in socioeconomic conditions, employment, lifestyle and classical risk factors on health and life expectancy. Such inequalities explain differences in life expectancy, potentially reaching several decades, between rich and poor countries (France vs Swaziland), but also within a given country (USA), a given city (Glasgow) or even a given enterprise (CERN) where all employees have the same level of healthcare insurance and access to treatment. Classical cardiovascular and neurovascular risk factors (smoking, arterial hypertension and lipid disorders) interact with socioeconomic status, intelligence, education, emotions and job responsibility/complexity, precipitating or preventing cardiovascular events. The same is true of dementia, for which midlife risk factors (obesity, arterial hypertension and hypercholesterolemia) should be considered in the psychosocioeconomic context, which influences cognitive reserves and thus affects the risk and severity of dementia in old age. Thus, in addition to lifestyle and classical risk factors, socioeconomic status appears as a major health determinant, by imposing behaviors and habits and by determining access to healthcare.