The social, behavioral, and economic (SBE) sciences have played an important role in determining the ways that people’s health is affected by a combination of genes and the environment,38 challenging long-held assumptions about what matters most to health. SBE research has also improved the identification of specific public health needs and ways to promote healthful behavior and prevent illness. Collaborations between SBE researchers and biomedical scientists have identified health problems and early death risks that are disproportionately experienced by large groups of Americans, enabling the development of strategic and timely interventions to improve their health and well-being. Two examples of such important contributions to knowledge include new understandings about how social relationships affect health and how groups of people in the United States differ in their mortality and health.
SBE researchers and neuroscientists working together have found a variety of ways in which behavior and biology affect each other. For example, adversities in life and how people perceive those adversities can determine whether genes are “turned on” (“expressed”), setting up conditions that affect health over the long term. Poverty, violence, and other sources of stress early in life alter children’s rapidly developing biological systems39 and leave them vulnerable to consequences throughout their lives, especially if the children are very young or experience multiple sources of stress—such as abuse and a chaotic home environment—at the same time.40 These discoveries have informed efforts to prevent child abuse and neglect; there is also good (and growing) evidence that newly developed programs and approaches can help children overcome the effects of these toxic forms of stress.41
Research at the intersection of behavior and biology has also revealed that social isolation is a risk factor for early death, comparable in magnitude to well-established risk factors, such as smoking, obesity, and lack of physical activity.42 In both adolescence and old age, the number and quality of people’s social connections have a strong and direct effect on cardiovascular, immune, and metabolic health, resulting in less hypertension, lower rates of inflammation, a lower body mass index (a measure of obesity), and reductions in metabolic syndrome (defined as increased blood pressure, high blood sugar, excess body fat around the waist, and abnormal cholesterol or triglyceride levels).43
In adolescence, social isolation increases the risk of inflammation as much as does physical inactivity. In old age, social isolation affects hypertension more than common risk factors, such as diabetes.
Identifying such risks in children before problems occur is critical for intervening early enough to prevent permanent damage to biological systems and avoid the costs they impose on individuals, families, and society.
Americans differ greatly in health and mortality depending on their social and economic circumstances, and these differences have widened in recent decades. For example, SBE research that compared generations born in 1912 and 194144 showed that, between these two generations, life expectancy at age 65 rose by 6 years for people in the top half of the earnings distribution, but by only 1 year for those in the bottom half. This finding is consistent with other studies.45
Some groups with lower levels of education, including middle-aged white women without a high school degree, have experienced rising death rates over the last two decades; opioids, suicide, and alcohol-related diseases have played a role in this trend.46 This and other findings about the health and mortality of the U.S. population provide important data for decisions about public health and government programs, such as Social Security, Medicare, and Medicaid.47,48