variety of diseases. However, both the Black and Health Divide reports found that behavioral choices are determined by one's material conditions of life, and these behavioral risk factors account for a relatively small proportion of variation in the incidence and death from various diseases. The materialist/structuralist explanation emphasizes the people's material living conditions. These conditions include availability of resources to access the amenities of life, working conditions, and quality of available food and housing among others. Within this view, three frameworks have been developed to explain how social determinants influence health. These frameworks are: (a) materialist; (b) neo-materialist; and (c) psychosocial comparison. The materialist view explains how living conditions – and the social determinants of health that constitute these living conditions – shape health. The neo-materialist explanation extends the materialist analysis by asking how these living conditions occur. The psychosocial comparison explanation considers whether people compare themselves to others and how these comparisons affect health and wellbeing. A nation's wealth is a strong indicator of the health of its population. Within nations, however, individual socio-economic position is a powerful predictor of health. Material conditions of life determine health by influencing the quality of individual development, family life and interaction, and community environments. Material conditions of life lead to differing likelihood of physical (infections, malnutrition, chronic disease, and injuries), developmental (delayed or impaired cognitive, personality, and social development), educational (learning disabilities, poor learning, early school leaving), and social (socialization, preparation for work, and family life) problems. Material conditions of life also lead to differences in psychosocial stress. When the fight-or-flight reaction is chronically elicited in response to constant threats to income, housing, and food availability, the immune system is weakened, insulin resistance is increased, and lipid and clotting disorders appear more frequently. The effects of chronic fight-or-flight is described in the allostatic load model The materialist approach offers insight into the sources of health inequalities among individuals and nations. Adoption of health-threatening behaviors is also influenced by material deprivation and stress. Environments influence whether individuals take up tobacco, use alcohol, consume poor diets, and have low levels of physical activity. Tobacco use, excessive alcohol consumption, and carbohydrate-dense diets are also used to cope with difficult circumstances. The materialist approach seeks to understand how these social determinants occur. The neo-materialist approach is concerned with how nations, regions, and cities differ on how economic and other resources are distributed among the population. This