This paper presents findings and arguments to show the power of social factors to affect health at the individual and at the national level. Social factors most strongly and negatively associated with health, at both levels, are those that indicate disorganisation and disruption, perceived helplessness and lack of support, low educational attainment, and poverty. Adverse changes in these social factors and their negative effects on health have been observed in many studies. When such adverse changes affect the lives and health of children, and those who will become parents, they affect the present and long-term future health of individuals because of the processes of biological programming described in this and other papers presented here. Such adverse changes in social factors also adversely affect the social circumstances of childhood, which in turn have a negative impact on health. Because changing social factors affect biological programming and social capitalisation, awareness of the health damaging effects of recent social change provides information on the future health of the population.