The scientific evidence is crystal clear: Early experiences literally shape the architecture of the developing brain. This widespread understanding is leading to increased public support for universal kindergarten to improve school readiness for all children and level the playing field for children facing adversity. But here is something less known to the general public: With the brain connected to the rest of the body, the first experiences affect all of our biological systems, for better or for worse, starting in utero and all the crucial years that follow.
This larger message sends an important wake-up call: We all need to start paying more attention to the science that explains how excessive adversity can harm lifelong health as well as early learning. . This knowledge can help us better understand why people of color in the United States are at higher risk for developing chronic diseases and aging prematurely than white people.
With growing evidence for the early origins of disparities in physical and mental health, focusing solely on brain development and learning only confronts one dimension of the pervasive racism-related inequalities that plague American society. Case in point: Although the educational achievement gap between black and white children has narrowed from 30% to 40% since the 1970s, reducing racial disparities in health has been more difficult. For example, premature births and low birth weight, which are associated with an increased risk of cardiovascular disease and subsequent diabetes, occur at a rate about 1.5 to 1.6 times greater in non-Hispanic blacks than among non-Hispanic whites, and these gaps persisted for decades.
A growing body of scientific evidence tells us that the foundations for lifelong health are built during the prenatal period and early childhood. Factors that promote positive outcomes include supportive relationships, safe physical environments, and sufficient resources to meet basic needs such as food and shelter. Take any of these protective factors away or add the weight of undue hardship or threat outside the family, and you tip the scales toward a greater risk of future problems.
Despite the critical influence of these early years, long-term results are neither inevitable nor biologically predetermined. Of course, physical and mental health is influenced by our genetics, but the chances of problems actually developing are strongly influenced by the environments in which we live. Policies, conditions and resources that address inequalities and ensure conditions conducive to healthy young children, as early as possible, will help build a healthier society. In other words, it is racism, not race, that is at the root of the persistent disparities in physical and mental well-being.
Race is a social invention. All humans, regardless of their skin color, share 99.9% of the same genome. Residential segregation – one of the many converging consequences of systemic racism, personal discrimination and poverty – leads to significant inequalities in exposure to air pollution, other environmental toxins and violence neighborhood, as well as unequal access to nutritious food, stable housing, and education and health care. The differences between blacks and whites in preterm births have been well documented and linked to the stress associated with discrimination, regardless of socioeconomic status. Black children are three times more likely than white children to lose their mothers before the age of 10.
How can the impacts of adversity from racism in early childhood affect the health of a lifetime? One answer lies in the particular sensitivity of young and developing bodies to the physiological effects of a stressful environment. We all know what stress looks like physically, and science explains the source of these sensations.
When faced with an acute challenge or threat, the stress response systems inside our bodies activate. Blood pressure and heart rate increase. Stress hormones such as cortisol are elevated. The immune system triggers an inflammatory response to prepare for wound healing and fight infections. Metabolic systems mobilize blood sugar to fuel the “fight or flight” response. Once the threat is managed, the stress response (which can save lives) returns to baseline. But if the level of adversity remains high for long periods of time (from chronic discrimination or poverty, for example), the continued activation of the stress response can have a wear and tear effect on the inside of the body that leads to “toxic stress” and a host of health problems.
For example, excessive inflammation can affect multiple organ systems and increase the likelihood of developing heart disease and autoimmune disorders. Prolonged elevations in blood sugar can lead to insulin resistance, obesity, metabolic syndrome, and diabetes. Once we understand the biology of adversity and resilience, we can see how the excessive activation of stress early in life does not lead to inevitable illness but increases the risk of later problems, many of which include the pre-existing medical conditions associated with more serious illness from Covid19. The high prevalence of these conditions among people of color may thus explain part of the marked racial / ethnic differences in hospitalization and death rates from the pandemic.
Much of the public debate on disparities in health outcomes focuses on unequal access to medical care, unequal treatment in the health system, and the impacts of lifestyles and individual responsibility on health. adulthood. But science tells us that preventing or lessening the effects of adverse experiences and exposures in infancy could be as important to long-term health as the conditions we live in as adults and the medical care we receive. .
A better understanding of how the synergistic tensions of systemic racism, interpersonal discrimination and intergenerational poverty can be integrated into the body can be a powerful tool on the road to a healthier and more just world. Science tells us that the road must begin in the first years of life.
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This article originally appeared in Known magazine, an independent journalistic company of Annual Reviews. Register to receive the newsletter.