Neighborhoods that were redlined in the 1930s still produce worse health outcomes nearly a century later. People living in these areas face higher rates of asthma, heart disease, preterm birth, and earlier death, not because of individual choices but because of lasting differences in environmental conditions, food access, and infrastructure that were set in motion by discriminatory housing policy.
Redlining was a federal grading system created by the Home Owners’ Loan Corporation (HOLC) that rated neighborhoods from A (“best”) to D (“hazardous”). Grade D areas, predominantly home to Black and immigrant communities, were denied mortgage lending and investment. The physical consequences of that disinvestment, including fewer trees, more pollution, less access to healthy food, and worse housing stock, persist today and translate directly into health disparities.
Hotter Neighborhoods, Less Green Space
One of the most measurable legacies of redlining is heat. A study of 108 U.S. urban areas found that formerly redlined neighborhoods are on average 4.5°F hotter than non-redlined neighborhoods. That gap comes down to concrete, asphalt, and the absence of trees. Nationally, tree canopy cover averages 40.1 percent in formerly A-graded neighborhoods and just 20.8 percent in D-graded ones, according to U.S. Forest Service data. Even if cities planted aggressively in these areas, the lower-graded neighborhoods have less available green space overall because of denser development and more impervious surfaces.
This isn’t just a comfort issue. Extreme heat raises the risk of heat stroke, kidney problems, and cardiovascular events, particularly for older adults and people with chronic conditions. And the lack of green space removes a buffer that helps filter air pollution, reduce stress, and encourage physical activity.
Air Quality and Asthma
Formerly redlined neighborhoods tend to sit closer to highways, industrial sites, and other pollution sources, a pattern that traces back to zoning decisions made when these areas were already considered expendable. Fine particulate matter (the tiny particles most dangerous to lungs) runs about 4 percent higher in D-graded neighborhoods compared to A-graded ones. That difference sounds small in percentage terms, but at the population level, even modest increases in particulate exposure are linked to higher rates of respiratory and cardiovascular disease.
The asthma numbers make the connection concrete. A study across eight California cities found that asthma-related emergency room visits were 2.4 times higher in formerly redlined census tracts: 63.5 visits per 10,000 residents compared to 26.5 in A-graded areas. After adjusting for other factors, living in a redlined tract was still associated with a 39 percent increase in asthma emergency visits. The gradient was consistent: C-graded tracts fell between B and D, suggesting a dose-response relationship where worse historical grades correspond to worse respiratory outcomes today.
Heart Disease and Blood Pressure
The cardiovascular effects of redlining are striking, and they fall hardest on Black Americans. Research from the Multi-Ethnic Study of Atherosclerosis found that Black adults living in historically redlined areas had significantly worse cardiovascular health scores than Black adults in A-graded neighborhoods, even after controlling for age, sex, education, and income. The specific metrics tell the story: Black residents of redlined areas had 78 percent lower odds of having healthy blood pressure and 60 percent lower odds of having a healthy BMI compared to those in the highest-graded neighborhoods.
In real numbers, Black participants in redlined areas had systolic blood pressure readings about 8 points higher and BMI about 2 points higher than their counterparts in A-graded areas. Blood pressure is one of the strongest predictors of heart attack and stroke risk, particularly among Black Americans, so these differences carry serious long-term consequences. Notably, the study found no similar association between HOLC grade and cardiovascular health for white, Hispanic, or Asian participants, pointing to the compounding effects of racial discrimination layered on top of place-based disinvestment.
Preterm Birth and Infant Health
Pregnant women living in formerly redlined areas face elevated risks for preterm birth. A Virginia study covering 2016 to 2020 found that women in D-graded neighborhoods were 36 percent more likely to deliver preterm compared to women in A-graded areas. They were also 20 percent more likely to have a low-birthweight infant, though that finding was not statistically significant. The pattern held across the grading scale: C-graded areas carried a 35 percent increase in preterm birth risk, and B-graded areas a 25 percent increase.
Preterm birth is the leading cause of infant mortality in the U.S. and raises the likelihood of developmental delays, breathing problems, and chronic health issues later in life. The environmental stressors concentrated in redlined neighborhoods (heat, pollution, limited access to nutritious food, housing instability) all contribute to the biological stress that can trigger early labor.
Food Access and Nutrition
Formerly redlined neighborhoods are far more likely to be food deserts, areas where full-service grocery stores are scarce and convenience stores or liquor stores fill the gap. Research has consistently found that predominantly white neighborhoods have roughly four times as many supermarkets as neighborhoods with large Black populations. In cities like Hartford, Connecticut, the pattern maps almost directly onto old HOLC boundaries: the suburbs surrounding the city, which are predominantly white and affluent with low unemployment, average four large chain supermarkets nearby, while inner-city neighborhoods that were historically redlined rely on small stores with limited fresh produce.
When healthy food is harder to find and more expensive to access, diets shift toward processed, calorie-dense options. Over time, this drives higher rates of obesity, diabetes, and the cardiovascular problems described above. It also creates a feedback loop: chronic disease makes it harder to work, earn, and move to a neighborhood with better options.
Shorter Lives
All of these disparities add up to measurable differences in how long people live. A large-scale study published in JAMA Internal Medicine tracked individuals who resided in HOLC-graded neighborhoods in 1940 and found that those in redlined (grade D) areas had an estimated 1.44 fewer years of life expectancy at age 65 compared to those in A-graded areas. At age 55, the unadjusted gap was roughly two years. Each step down in HOLC grade corresponded to about half a year of lost life expectancy, meaning the relationship was consistent and graded rather than a simple redlined-versus-not divide.
Even after adjusting for individual characteristics like sex and race, the gap persisted. At age 55, each one-grade decrease in HOLC rating translated to 0.57 fewer years of life. For someone in a D-graded area compared to an A-graded one (a three-grade difference), that works out to about 1.7 fewer years of life, solely attributable to the neighborhood’s historical classification.
Why the Effects Persist
Redlining was officially outlawed by the Fair Housing Act in 1968, but the mechanisms it set in motion are self-reinforcing. Disinvestment led to lower property values, which led to a smaller tax base, which led to underfunded schools, fewer public services, and deteriorating infrastructure. Highways and industrial facilities were routed through these neighborhoods because land was cheap and political resistance was low. Residents who could afford to leave did, further concentrating poverty.
Today’s social vulnerability indices, including the CDC’s Social Vulnerability Index, show strong correlations with historical HOLC grades. Neighborhoods graded D in the 1930s are still more likely to score high on measures of poverty, minority concentration, housing burden, and limited English proficiency. The policy is gone, but the geography of disadvantage it created remains largely intact, and so do its health consequences.