Low-income Americans also have higher rates of behavioral risk factors—smoking, obesity, substance use, and low levels of physical activity—which are powerfully influenced by the more challenging home and community environments in which they live. For example, poorer neighborhoods have a higher density of tobacco retailers, and the tobacco industry has historically targeted low-income people through various marketing strategies. Low-income people may also have limited access to cessation counseling services and pharmacotherapies and may experience higher levels of chronic stress—all of which make it more difficult to stop smoking. Perhaps unsurprisingly, people in families that earn less than $35,000 a year are three times more likely to smoke as those in families with an annual income of more than $100,000.
Low-income communities also contend with other structural challenges that contribute to higher rates of obesity and chronic disease, including less access to fresh foods; a higher density of fast-food restaurants; and a built environment that is not conducive to physical activity, with less open space and fewer parks and sidewalks. As a result, poor adults have higher rates of obesity and are less likely to meet guideline-recommended levels of physical activity, compared to other adults.
More broadly, low-income Americans encounter numerous daily environmental exposures that create greater allostatic load—the wear and tear on the body that accumulates with repeated or chronic stressors. The communities in which low-income people live have higher levels of violence, discrimination, and material deprivation—including the lack of housing, heat, water, and electricity. These communities have more environmental pollutants, underresourced schools, and higher rates of unemployment and incarceration. For residents with a home, the threat of eviction is commonplace, as more than one in five renting families in the United States spends half of its income on housing. A robust literature links chronic stressors, including financial hardship, to deleterious genetic and hormonal changes—such as impaired DNA repair mechanisms and higher cortisol and adrenaline levels—that increase the risk of chronic disease. The negative cardiometabolic effects of poverty seem to start early and continue throughout the life course.