If Not Genetics, Then What? Biological Pathways and Population Health
This chapter reviews the understanding of relevant phenomena at the cellular or subcellular level within individuals. Some of the biological pathways to heterogeneity in health status are quite obvious. Dominance, or Type A behaviour, or hyper-reactivity, or personality generally, has a significant genetic component. The biological pathways through which environmental and social factors have their effects may be found in the ways in which humans and other primates respond to stress. The demonstration of linkages at the cellular level between the nervous and other body systems obviously provides an important link in the chain from social environments to biological effects. A slightly different perspective on the same issue is introduced in a recent review of the relationship between "Control and Health". The human personality studies indicate that turning one's anger inward is even more harmful to one's health than letting it out. So humans, like monkeys, baboons, rats, and dogs, may respond to a stressful environment that they cannot control with physiological changes that are harmful to their health.